A day in the life of a SeaLifer!


Nathan Hill grabs at the chance to return, if briefly, to work in public aquaria — and is left breathless by a hectic schedule.

From the position of spectator, the job of an aquarist is a hobbyist’s life of bliss. The illusion of playing with hi-tech gadgetry, embarking on elaborate breeding and research projects and frolicking with ocean giants is one that many a layperson covets.

For visitors, public aquaria don’t seem particularly hectic places to work. Guests rarely see panicking staff dashing from leaking pipe to leaking pipe, or catching fish. Everything seems to occur in a quiet and hidden harmony behind the scenes.

Having been out of the public aquarium trade for more than a decade, I decided I wanted to return to see how things play out day to day.

Even so, I fancied myself as more than a tourist, so contacting London SeaLife curator Paul Hale — who used to be the curator of the aquarium where I once worked — we arranged for me to be thrown into the mix of staff.

I’d do what the employed team of SeaLife staff would do, facing the same highs and lows, and be exposed to the same risks. This was to be no cosy, mollycoddled day of being shown things from a distance while health and safety managers fretted over whether my shoes were comfy enough. This was a chance to get stuck into the hard core of public aquatics.

I was tossed from aquarist to aquarist and job to job. Some were familiar and, just like riding a trike, I was comfy within seconds, flaunting skills I haven’t had to dust off for many years. Other tasks were newer and more daunting — not to mention much more perilous than I ever remembered.

Most importantly, and that part of public aquaria I’d forgotten about, by the end of my shift I was totally exhausted!

A combination of carrying buckets of water, going from extremes of tropical heat to Arctic cold and constantly being on my feet chiseled away at my energy until I remembered just how draining a job it really is.

9am: Start the day
I turned up late and missed the first task — checking the life support and livestock.

Don’t think this is comparable to a quick glance inside a 60cm/2’ tank to look for whitespot. This is a rare chance to have an unhindered look at sharks and rays in 1,000,000 l/220,000 gal of water to spot the odd parasite or split fin.

An hour later and such inspections would be tricky, once the doors are open and visitors arrive, so inspection needs to be accurate but fast.

Life support checking is just as laborious. Rather than having a Fluval 2 canister, the tanks involve gigantic spider valves, pressurised sand filters and hundreds of metres of plumbing. A simple leak can fast turn into a headache that requires day-long attention.

9.30am: Feeding jellyfish and quarantine
Unlike sprinkling some flake on to the surface of an aquarium, breakfast for livestock takes considerably more preparation.

In a dedicated live food section, we harvested Artemia nauplii — litres and litres of nauplii. Fixed plumbing accelerated the process as we drained vats through nets and then separated the newly-hatched shrimp.

We used magnetised Artemia and so, once harvested, we placed the culture into a settlement tube teeming with magnets. This drags out the cysts and unhatched eggs, but not hatched shrimp.

As the Artemia settled, we cleaned the harvesting vats using algae pads and dexterous fingers. Then the vats were refilled with reclaimed seawater from a plumbed supply and fresh cultures soaked for the next day.

We enriched adult Artemia with lipids, while constantly keeping an eye on tanks brimming with shark eggs, as well as tanks of pipefish, and the various animals being rested. We strained off the now shell-free Artemia nauplii and started syphoning out debris from jellyfish tanks before feeding them.

More cleaning followed as the magnets were washed off and Artemia separator cleaned out, followed by more feeding. Some food was held back for display anemones and other jellyfish.

Gaining access to the feeding areas for displays took as much flexibility in moving around pipes and other behind-the-scene obstructions as manoeuvring around the newly-arriving visitors. Wearing a SeaLife top is a visible invite to approach and converse, that’s for sure.



10.40am: Main feed preparation

My quarantine session finished after the records had been filled in and I moved to the next task where we were to arrange meals for the larger displays.

Big fish have big appetites but, with so many in the larger displays, meals have to be able to fit different-sized mouths.

For the one tank, we had to arrange supplements in the food — specifically vitamins and potassium iodide. The latter is required for sharks that are notoriously prone to developing goiter — over activity of the thyroid gland.

Individual food fish were incised, supplements measured and the whole lot assembled by hand. We prepared 20 mackerel, 15 whiting, nine haddock, two trevally and almost 9kg of squid.

Some was chopped in the normal way. Others had heads removed before being gutted and cut into strips of varying sizes. With endless squid this was no quick task.

Obviously this job was filthy, requiring gloves and aprons. Despite these, the liquids and their associated aromas still found their way into my clothes and skin, making whoever performs this task regularly an aquatic pariah.



11.40am: Water testing

Next came the closest thing to a break so far — a sit down in the lab to test water.

Water tests are frequent in public aquaria and records comprehensive. The kit here is a step-up from an off-the-shelf master tester and regular tests take place for NO3, NO2, NH3, Fe, SO4, Cl, K, PO4, Cu, Alk, Mg, S.G, and pH.

Some things we could probe, such as nitrate, but for other tests we had to use colourmetric indicators — just like a home test — and then get an accurate reading by placing them in a photometer. Everything had to be recorded. Test tubes and beakers were everywhere and we worked through the lot.

The job was made longer by the need to rinse everything thoroughly between tests. With the ultra-accurate readings of the photometer we used comes a need for complete cleanliness — and lots of wiping up afterwards.

Thankfully we only had a few sections of the aquarium to work through as the duties are rotated daily, but this would easily become a full-time job for any employee if all the systems needed to be recorded daily to this high degree of accuracy.


12.30pm: Penguin feeding
Think that being an aquarist is all about fish? Think again. In the ever-changing climate of public aquaria diversity is essential and even though you may be qualified in fish you’ll likely meet and work with other animals.

The chilled section of the penguins is a brief relief from the heat of other sections, but the labour is just as intensive.

As well as feeding we had to collect ice prepared in another part of the labyrinthine building. We then had to lug it to the other end to drain off excess fluids before heading to the display where we had to don lifejackets.

My second chance to sit down was particularly cold comfort, as all I had to perch on were frosty rocks. I sat shivering as the animals came and took food that had to be rammed down their throats because of their avian laziness.

Post feed, we had to collect and distribute the ice — a delightful task for already chilled hands. Once deposited, there were more records to complete and more cleaning before we broke for lunch. Yet even that wasn’t simple.

Public aquaria get through lots of food and en route to our break we met a pallet of frozen fish and squid, and a handful of staff unloading it. We were instantly collared into lifting ice cold, heavy boxes into the storage freezers — marking and recording everything along the way.



2.30pm: Shark feed

This was the high point of the day, but not as relaxing as a feed session in a home tank. We had to carry buckets across the building and then go behind the scenes into the feeding platforms of the Pacific display tank.

Lifejackets on, we stood in remarkable heat and humidity working collectively to feed the fish. Radio communication from below allowed for targeted scatter feeding, while I knelt on painful, grated flooring to dangle a long feeding pole over the sharks.

I needed to make sure that the food didn’t go to the wrong shark, but I failed. Identifying individuals at a few metres depth, when looking through waves, is not a chore I’d relish again.

Improvisation was key, chasing up and down service walkways above the tank, trying to feed the right fish in oppressive heat. Suitably convinced that all had eaten, we returned the gear to the food preparation area for more cleaning and yet more records.

3.15pm: Moving fish from quarantine to displays
For most of us moving fish would be simple, but usually a crocodile isn’t involved!

Although a peculiar choice, we had to round up some Malawi cichlids from the quarantine area, which involves bringing a bongo to half fill with water — probably to 60-70 l/13-15 gal — and then catch the fish to put inside.

While doing so I took the chance to see some of the ever-problematic big rescue fish in large rounded tubs. There was a gar in one, maybe 1m/3.5’ long, that the former owner kept in her bathtub…

With the fish eventually caught and the bongo loaded onto a trolley, we made our way through the maze of back passages to the crocodile display. Behind the scenes again, we had to bring the bongo to within dripping range, as carrying the thing through the restrictive openings in and out of the display would have been well nigh impossible.

Satisfied we were within several metres, a length of hose was used to lift water from the system and drip into the bongo.

After being briefed on seemingly endless handling protocols —including one explaining what to do while having your arm pulled off by the crocodile — it was a case of luring her into an area which could be remotely closed off.
A game of patience ensued, with aquarists grabbing at levers to lock her away.

We performed a clean, using long wipers and scrapers on poles. Reaching both into and out of the water using a 3m/10’ pole is exhausting at the best of times, but, combined with the tropical temperatures and humidity generated by hidden misters, it becomes particularly unbearable.

After using the drip method for around 40 minutes, the fish were transported to smaller buckets where they were then carried through the narrow access way and released.

It was with some shame that I’d taken too long on this chore as I had actually been destined to remove shark and ray eggs from another tank — a job that, as a result, I missed…

4.20pm: Ocean tank feed
Laden with yet more trollies and buckets of food, we headed across to another gigantic display housing turtles. This time we were armed with both New Era pellet foods, as well as ample greenery in the form of cabbages, cucumbers and more.

Without the benefit of the radio communication this time, we had to simply assess whether the fish were getting the right foods. Much involved scatter feeding, hurling handfuls into the frenzied mass. It was impossible to spot if anyone was missing out.

My role was to distract the two huge Green turtles by feeding them greenery while my co-worker ran a long pipe to the bottom of the tank, dropping food down to more benthic fishes.

Easier said than done, as these diners spent as much time chasing the tube as accepting my offerings!

More scatter feeding ensued, with chopped squid and fish creating yet another frenzied flurry of excitement.

4.50pm: Target feeding the sharks
We returned to the Pacific display as we travelled back from the turtles. Not content that by now everything had a full belly, my colleague had held on to a few fish to feed a couple of specific Black-tipped reef sharks.

While scampering along, I peeked into one of the display filters which looked as though it had more flow than most rivers I had yet come across. I realised then just how deafening that half of the display was and how easy it would be to run into difficulties without being able to communicate your distress to any colleagues.

Target feeding done, we made our way back to the food prep area to sift through uneaten food and store what could be used next day, and clean our buckets and equipment before finishing the day with a final huge dose of yet more record keeping.

Why do the staff want to do it?
As I was working alongside such a wide range of aquarists, I asked what made them buzz – and what deflated them.

Major plus point was the experience itself. Several times my co-workers became dreamy eyed when talking of the magic of working alongside the animals. After all, not many of us get to keep a Sand tiger shark!

One aquarist talked of the sheer diversity of experiences, always trying new things and never tethered to a dead-end job.

Sensations
Big tanks bring a wealth of new sensations and one worker beamed as she talked of diving in the gigantic, shark-filled tanks.

Another explained that his high point is educating the public. He thrived on breaking visitor misconceptions about creatures like sharks and felt a sense of reward when they left for home far wiser.

However, there are also some lows and most loudly voiced was the amount of paperwork associated with the job.

Pay was an obvious gripe too. Working in a role you enjoy, but knowing so many people want your job, you might not always have financial leverage over your employers.

Abrasive visitors was another — a point I’m sure many retailers could sympathise with. Those who have no compassion for the animals have no bond with those who love them.

All-day smells
Cleaning was another bugbear and, given those endless buckets of slimy squid and fish offal, I can see why. The smell sticks with you all day…

The final gripe was the number of working hours. Those in public aquaria have a greater obligation to work weekends and bank holidays and finish only when the animals have finished needing them.

Given a crisis, you could still be there well into the night. Breeding sharks don’t acknowledge clocking-off times...

Interested in a job like this?

Being a public aquarist is enjoyable, but not something to just walk into.

Work experience is vital, given the hands-on role dealing with animals that can cause you serious harm.

Qualifications are becoming ever more essential and a good grade in a specialist field would be advantageous.

Staff members were mainly from marine biology backgrounds, although zoology and even psychology degrees were also in the mix. Some had worked at internships elsewhere and others had started working on the most menial tasks.

It might help to be aspirational too. Nearly everyone I spoke to eventually wanted a much bigger role in aquatics, citing marine conservation, aquatic research and even their own curator’s job as end goals.

Don’t expect this to be a glamorous occupation. Public aquarists don’t live in mansions and drive Bentleys. They tend to be from the school of life background, appreciating that this is definitely a labour of love.

Would I go back to it? Hell, given the choice I’d be chopping squid right now…

Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.

Meet the morays


Be fully aware of what you’re taking on if planning to keep a moray eel. They need minimal maintenance but that fearsome reputation is well earned. Dave Wolfenden explains more.

Moray eels are seen as creepy, scary or just plain cool — perhaps all at once. Yet some can be suitable for appropriate home aquaria.

There are more than 100 species in the family Muraenidae. Being scale-less and lacking the pelvic, pectoral and pelvic fins of most other fish groups. They have highly developed dorsal and anal fins which can undulate when swimming.

Their general morphology, however, is an adaptation to a fairly sedentary lifestyle — being 'sit and wait' ambush predators.

Morays suffer a formidable reputation, which isn’t helped by their intimidating appearance. When ambushing, most poke their head out of their hidey-hole and expose fearsome fangs. This is simply the moray breathing, passing oxygenated water over its gills and out through the tiny gill openings.

Having said that, morays have been responsible for numerous ‘incidents’ involving divers, usually as a result of careless poking in the moray’s lair, or through hand feeding.

The legacy of a large moray’s bite isn’t pretty. Those needle-like teeth can cause severe damage and some victims have lost fingers, thumbs and sometimes more as a result. There’s the additional risk of aggressive secondary infection, courtesy of a mysterious cocktail of bacteria in the eel’s mouth.

Avoid hand feeding. They can move exceedingly quickly and their poor eyesight means they can’t readily distinguish between food and fingers. So use a feeding stick, or, better still, tongs when feeding and always keep your wits about you.

Feeding twice a week should be more than adequate for most adults and around three times a week is fine for youngsters. It’s not unusual for new acquisitions to go on hunger strike for several weeks after introduction to new quarters, so it may be necessary to train the moray onto captive diets.

Regular presentation with feeding tongs — and a lot of persistence — may be necessary. It’s rare for them to starve to death, so keep plugging away until they feed!

They need space!
Despite their sedentary nature, morays demand a lot of space and smaller species can be kept in systems at a minimum 250 l/55 gal. Larger morays require correspondingly sizeable housing and I wouldn’t consider keeping a Leopard moray (Gymnothorax favagineus) in an aquarium less than 1500 l/330 gal.

Aquascaping must take into account natural habits — so incorporate some lair, which could comprise some carefully arranged rockwork. Be warned, however, that morays are extremely strong, so a lovingly constructed cave can rapidly become rubble. Fixing rockwork with epoxy putty can provide a solution.

A more elegant method of creating a suitable captive habitat is to employ flexible plastic drainage pipes. These can be cut to length, bent to shape and incorporated into the rockwork. Both ends should be exposed to permit adequate water circulation and prevent build-up of stagnant areas or collection of uneaten food or detritus.

The pipes could be embedded in the back wall of the aquarium, or a series can form the basis of a central rockwork feature on the base of the tank.  A little planning and creativity can help to make an attractive display which any self-respecting moray will love.

Lighting can be relatively subdued to ensure the moray is on display as much as possible. Intense metal halide lighting can simply encourage specimens to hide.

Secure the lid of the tank firmly. Morays are escape artists, as I know. Picking a crispy moray from the floor isn’t gratifying, so ensure any gaps are sealed.

An eel can use its tail and powerful, muscular body to lever the lid off a tank, so it will need to be sturdy. Public aquariums keeping the larger species may even bolt on their lids!



Water quality

Even the smallest species is a relatively large fish compared to most other species commonly kept and, as such, their feed input and waste output is pretty prodigious. Filtration must cope with the large quantities of solid waste these fishes generate, so mechanical media needs to be suitably efficient and cleaned regularly.

Consider the quantities of ammonia that can be generated — and that includes potentially dangerous ‘spikes’ after meals. Extremely efficient biological filtration is also a must, with an adequately sized external canister or trickle filtration being ideal, and ensure a high turnover for adequate oxygenation.

Don’t even consider a moray without a preferably oversized protein skimmer. As an additional tool for water quality ozone could be considered, in conjunction with skimming, to deal with the high bioloading these fishes are capable of exerting on the filter.

Monitor alkalinity and pH, as it’s easy for values to fall outside optimal with a high biomass.

Healthcare
Morays are happy with minimal healthcare and, once settled in, are hardy. In fact, providing filtration is up to the job and water quality is optimal, these are among the most bulletproof of marine fish.

These eels respond poorly to copper-based treatments, presumably because of their scale-less skin. They rarely suffer from whitespot or other parasitic diseases in any case, but alternative treatments should always be sought and care taken not to overdose with any remedy.

Bacterial conditions may occur, especially if trauma is sustained during handling and transport or if water quality dips, and they respond well to antibiotics. Always quarantine new specimens.

When selecting stock, try to undertake a thorough inspection of the whole animal. This may mean asking for it to be coaxed out of its hiding place in the dealer’s holding tank. Check for physical damage, for example around the mouth, and signs of eye cloudiness.

The best form of healthcare is prevention through adequate space, suitable aquascaping and maintaining optimal water quality.

What to feed
Morays diet varies. They’re all carnivorous, but some require a crustacean-based diet while others will favour fish or squid.

The greatest clue to any species’ diet is dentition. Crustacean feeders tend to have flattened teeth for grinding and crunching hard-shelled invertebrates, while the needle-like teeth of piscivorous species are used for spearing and gripping slippery prey.

Whatever the diet of your chosen species, variety is important. Specialist crustacean feeders should have a range of prawns and crabs. Piscivores will benefit from a mix of frozen fish species as well as squid. Vitamin supplementation should be considered for all morays to prevent dietary deficiencies.

Tank mates?
Tank mates should vary, depending on species and diet and smaller, crustacean feeders can co-habit with a range of fish species and sessile invertebrates, although they may eat very small fish.

Larger, more predatory morays need to be kept in either a species aquarium or with robust, aggressive or semi-aggressive species. Porcupine fish, puffers, lionfish and triggers can be good choices of companion — providing they’re not meal-sized.



Which system is best for them?

Can morays be maintained in a reef system? It’s possible for the smaller species, notably the Snowflake, Echidna nebulosa, but filtration still needs to be able to cope with relatively high waste outputs.

For larger morays, such as the Leopard, Gymnothorax favagineus, maintaining water quality suitable for invertebrates becomes much more of a challenge.

Realistically, you’ll want to consider these specimens for a fish-only system and species or mixed large ‘predator’ set-ups will be the best route.

Can I breed moray eels?

Morays have yet to be successfully bred in captivity — and for a pretty good reason. It’s down to a bizarre planktonic larval stage, known as the leptocephalus, which the juvenile eels assume as they drift for weeks or months before metamorphosising.

Providing conditions for successful development of the leptocephalus stage in captivity represents a huge challenge, and it looks as if captive moray breeding will elude us for some years yet...

Meet the family
...or at least some of them. Only a handful of morays are commonly available in the trade and the large nature of most species precludes them from being kept.

Here’s a selection of some suitable and not so suitable species you may find a home for:

Justifiably the most popular species in the hobby is the Snowflake eel, Echidna nebulosa (pictured above by Prilfish, Creative Commons) from the Indo-Pacific and Eastern Pacific.

This beautiful, hardy species has plenty to recommend it, growing to a manageable size and rarely reaching over 50cm/20”. It’s a crustacean feeder and, provided there are no crabs and prawns in the aquarium, they are peaceful. Just ensure any fish tank mates are not mouth-sized — just in case!

In fact, it’s possible to maintain Snowflakes in reef systems, providing your filtration is up to the task. They won’t bother sessile invertebrates, but some creative aquascaping will be required to provide them with a dimly lit lair if keeping them with light-loving animals.

The Zebra moray, Gymnomuraena zebra, has a similar distribution and grows to around 90cm/35” in captivity. It’s another crustacean feeder and generally peaceful mixing with larger fish species.

Their size makes them less suitable for reef systems than the Snowflake, with fish-only being the set-up of choice. Obviously, don’t keep them with any crustaceans either!

Many aquarists covet the Dragon moray or Japanese dragon eel, Enchelycore pardalis (pictured above) and it’s easy to see why. With its psychedelic mottled coloration of orange, black and white and its prominent nasal ‘horns’, this is a real stunner.

Hailing from the Indo-Pacific, it is a piscivorous species, reaching around 60cm/24” in length, sometimes more.

Expect to pay top dollar for one — and a £1,000 price tag is not unknown!

A ‘budget’ alternative is the Mexican dragon eel, Muraena lentiginosa (above) from the Eastern Pacific, and it’s another piscivore. While not as attractive as the ‘true’ dragon eel, it is still handsome, attains a similarly manageable size but has a far less hefty price.

Many Gymnothorax species are just too large and aggressive for most hobbyist systems, but a few are suitable for those with enough space and equipment. The Golden eel, Gymnothorax miliaris (pictured above by Nick Hobgood, Creative Commons) is an attractive species from the Western Atlantic and it grows to around 70cm/28”.

It’s occasionally offered in the trade and is a particularly good choice. Feed a varied diet of frozen, supplemented fish and squid to make this eel happy.

From the Indo-Pacific, the Leopard moray, Gymnothorax favagineus,  is a hardy predator, but bear in mind that these grow to well over 80cm/32” in captivity. They’re also very girthy and capable of producing prodigious amounts of waste.

These are probably the largest morays that could reasonably be considered for the hobbyist.

They are relatively easy to maintain, but need to be kept in very large systems with robust tank mates and efficient filtration. Feed squid and fish twice a week —and mind your fingers at all times!

The Ribbon eel, Rhinomuraena quaesita (pictured above by Chika Watanabe, Creative Commons) is one to avoid. With its bizarre nasal extensions, it certainly looks fascinating enough, but Ribbon eels are difficult to maintain, with starvation the major cause of death among captive specimens. Some success has been reported with those in public aquaria — but pretty dismal survival rates are the norm.

Thoroughly research and identify any specimen before committing to ownership. Various unusual species occasionally turn up in the trade and positive ID is essential to determine potential adult length. Some reach hefty and downright unmanageable sizes — often with aggressive dispositions.

Just because a specimen is offered for sale, don’t automatically assume it’s suitable for the home aquarium. You have been warned!

Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.

Go rockpooling this weekend!


Make the most of the gorgeous weather. Relatives of what we keep at home can be found in our rock pools. Richard Aspinall reveals why he loves to be beside the seaside.

As my interest in reefkeeping has grown and my bank account has shrunk proportionately, I’ve rediscovered rock pools. These wonderful features of our tidal and rocky shores that are neither land nor sea cradle a wealth of life inhabiting our inshore waters.

We can also meet some of the distant and slightly more rugged relatives of the creatures we keep in our reefs back home.

My interest in the sea started when I was young, but growing up in a northern mill town did not offer many opportunities to explore reefs — except for that one miraculous week of the year when we packed ourselves on a train and headed coastward.

 

For kids and adults alike, rockpooling consists of stuffing as many crabs as possible into a small and rapidly overheating bucket. That kind of rockpooling wasn’t for me though.

Crabs were of little interest. I was looking for blennies, anemones, starfish, fan worms, swimming crabs, snails, Sea hares and so on...

I’ve met a few fishkeepers who’ve loved getting their hands wet around our British coastline, but for those of you who haven’t sampled this fascinating, largely free and only mildly perilous activity, here’s a quick introduction to some of the critters you can find in these pockets of water.

Fish
Dozens of fish species inhabit our rocky shores, with wrasses such as the Ballan (Labrus bergylta), Corkwing (Crenilabrus melops) and Painted (C. tinca) being equally as colourful as many tropical species.

The average rockpooler though is more likely to come across marooned bottom dwellers. Blennies such as Parablennius gattorugine  — the Tompot (above) — are common and remarkably attractive.

Southern coasts may reward the pooler with Butterfly blennies (B. ocellaris), a species having a gorgeous ‘eye-spot’ on its dorsal fin, or Montagu’s blenny (Coryphoblennius galerita).

Crustaceans
Crabs regularly feature in the trade, though we usually offer homes to smaller, herbivorous or detrivorous species such as Mithrax or species from the Porcelain crab group — not forgetting our beloved hermits.

Parting the seaweed and carefully lifting it aside, however, could reveal several much bigger and equally interesting species — more often than not the common Green shore crab, but occasionally rarer species such as the small Hairy crab (Pilumnus hirtellus) or tiny Pea crabs (Pinnotheres sp.) that live commensally in the shells of bivalves. There’s also the exquisitely marked Marbled swimming crab (Liocarcinus marmoreus).  

After the shore crab the most commonly found are small specimens of the Edible crab (Cancer pagurus) and the dapper Velvet swimming crab (Necora puber). This is a splendid creature with red eyes, shot through with blue on the legs and with flattened oar-like rear legs (periopods) to help it move at considerable speed through the water.

One of the joys of rockpooling is the chance to meet larger versions of creatures we wouldn’t entertain in a captive reef.  

A big crab is a nightmare to house and feed — and hard to love — but just catch one, briefly and carefully, and marvel at its construction. It has remarkably ‘engineered’ joints and pincer pivots, wonderful detail in its eyes and a breathtaking complexity of scores of separate ‘plates’ that make up its skeleton.

Our waters also offer a wealth of hermit crabs, which can usually be found in pools as smaller specimens inhabiting the shells of shallow water molluscs such as the Common periwinkle (Littorina littorea). Shells of deeper water molluscs, such as the Common whelk (Buccinum undatum), are much sought after below the low water mark.

The larger crustaceans don’t represent all of the order. Amphipods, ostracods and isopods can found by the more enthusiastic pooler, while several Palaemonid, Hippolytid and Alpheid shrimps can be found around our coastline, though the commercially valuable and very common Brown shrimp (Crangon crangon) is often found in the greatest numbers.

Occasionally, extreme low tides may reveal a Squat lobster (Munida sp., Galathea sp.) or even a Common lobster
(Homarus grammarus).  

Divers often take ‘lobbies’ for the table but, if you must do so, research first and ensure you take only older larger specimens that have had chance to breed — and that you are legally able to do so. These amazing animals should be left well alone!

Corals and anemones
We often associate anemones with warm tropical seas and colourful clownfish, but our temperate waters are replete with anemones, some exceptionally beautiful. The commonest and most easily spotted in the rock pool is the vivid red Beadlet anemone.

This resilient species can survive many hours of exposure to air, baking sunlight and freezing winds, before the tide returns and this small 5-8cm/2-3” creature opens its tentacles to feed in the manner we are all familiar with.

Warmer coastlines on the south and west of the UK might reveal a Daisy anemone (Cereus pedunculatus) buried with its foot in the sand, while, below the low water mark, rocks and harbour sides can be covered in Dahlia anemones (Urticina felina), Plumose anemones (Metridium senile) and one of our few stony corals — the Devonshire cup-coral (Caryophyllia smithii).

Soft coral species are limited in number, but not necessarily in biomass. Alcyoniums, such as the Dead Man’s Fingers often inhabit kelp forests and may cover many acres of shallow water all around the British coastline.

Echinoderms
Poolers are likely to come across several starfish species, from the Common (Asterias rubens) to some Cushion stars from the familiar genus of Asterina.

Extreme low tides may reveal some rarer and larger starfish, such as the very spiny and quite large Marthasterias glacialis or the smaller and attractively coloured Henricia starfish.

Several species of Brittle stars can be found in British rock pools — Amphiura brachiata, A chiajei and A. filliformis being common smaller species.      

Sea urchins are not commonly found alive in rock pools, but the remains of their ‘shells’ are common and intact skeletons are likely to be found in those seaside curio shops.

Molluscs
Nearly every genus of creatures we keep in our tanks has representatives in UK rock pools and this is much the same with the molluscs. You’ll be lucky to find turbos (order Turbinidae) as the few species in Europe favour warmer waters, but you will find cowries, trochids (Top shells), a cerith or two and nassarids such as the Dog whelks (Hinia sp.) and, if really lucky, a Sea hare.

Most are grazers, such as limpets, winkles and top shells. Look out for the chitons — small, oval, flattened grazers with shells made from eight plates that allow the creature to flex as it moves across the rock.  I’ve found the occasional one on live rock but never managed to keep them alive, suggesting their dietary needs are more complex than grazing algae and diatoms.  

Also look out for Blue-rayed limpets (Helcion pellucidum). These tinies are often found attached to the stalks of large sea weeds and have neon blue spots arranged in ‘rays’ radiating across the shell.

Rockpooling dos…

  • Check tide times.  
  • Be patient. Move seaweed and rocks aside slowly and watch for movement.
  • Put rocks and seaweed back where you found them. Many creatures will survive under seaweed when the tide is out, but not in full sun.
  • Make sure you put back anything you catch promptly and carefully.
  • Take care underfoot. Falling over on a rock covered in barnacles will not help you maintain your beach beautiful body.

…but don’t

  • Wander out to the furthest pool you can find as the tide starts coming in.

 

10 great places to go rockpooling

  • Cresswell Shore Nature Reserve, Northumberland
  • Flamborough Head, Yorkshire
  • Thanet, Kent
  • Samphire Hoe, Kent
  • Seven Sisters Country Park, Sussex
  • Charmouth, Dorset
  • Shoalstone Beach, Devon
  • Helford Passage, Cornwall
  • Portrush Nature Reserve, Northern Ireland
  • Rockcliffe, Kirkcudbrightshire, Scotland

 Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.

A magical reef tank


Dreams can become reality if you invest in the right equipment. Nathan Hill drools over the magical reef tank of D-D’s Stuart Bertram. And you can see more of it on the video at the end of the feature.

I’m not usually a jealous man, but when my editor sends me out to look at certain tanks I can’t help but covet them.

My excursion to see the home project of Stuart Bertram, co-director of D-D The Aquarium Solution, filled me with a desire for a leviathan of my own — only to know that I’ll never fulfil it.

Those aware of the people behind D-D will already be aware of the jewel that is the tank of managing director David Saxby. Although not on the same, gargantuan scale as David’s, this is nevertheless a tank that makes knees go weak.

Both photographer Neil Hepworth and myself were stunned into silence when shown the aquarium room. Stuart has good reason to be proud. Inside the 2,200 l/484 gal reef set-up are some of the most developed corals I’ve yet witnessed, a cloud of fish nigh on impossible to count and a gigantic clam that doesn’t look out of place in these surroundings.



Special achievement

Amazingly, almost everything in the tank has been grown from tiny frags which Stuart cultivates himself. To see the size of the small-polyp-stony corals within, and to know that they all emerged from tiny shards, leaves any observer with a sense that something very special has been achieved.

In fact, as Stuart himself notes, the only problem is that the tank has now reached the stage where corals have grown so successfully that they are in danger of shadowing themselves out and starving their own, lower polyps of life-bringing light. We were shown some areas — hard to spot if not consciously looking — where this has started to happen.

It’s unusual to find a reefkeeper who complains about delicate corals growing to the point of nuisance, but this is what has happened with pulsing Xenia which is periodically harvested to stop it behaving like a weed.

The Xenia is even taking over one of the sump tanks, where Stuart rears his home frags in the water supplied by the reef above and bathed in the light of a single, 400W Giesemann metal halide. All corals down here are growing fast, literally with no home to go to, as all space is accounted for in the tank proper. Stuart trades these inverts with local retailers for fish.

The life forms in this tank have taken hold incredibly fast, given that the project only started in February 2009. Initially, Stuart had installed a different tank, but there was domestic conflict involving the degree to which this aquarium encroached on living space.

He sought to resolve the issue with a larger, equally customised tank in its own dedicated room. This was originally a garage and subsequently converted to match the feel of the tank.

The 2.2 x 1.5 x 0.72m/7.2 x 4.9 x 2.4’ custom built Deltec aquarium would have posed a problem to most home aquarists, and even here it was tricky getting it through the garage door. The fit was so tight that, using a pump-truck, the pallet had to be cut away from beneath for the tank to be set down.

Once in place, feet within the frame could be adjusted for balance and equipment installed. For a tank of this size, glass bracer bars are too brittle, so instead of transparent beams running across the top, taught metal cables run from side to side and lengthwise.

Despite these cables, pipework and live rock was installed, and 350kg of live rock supplied by Calico was glued into place around the piping — creating a rockwork frame on back and sides, as well as an elevated area that sits centrally. Looking at the pipework now, it is hard to discern where pipes end and corals begin.

Because of the size of tank and close proximity to the wall, Stuart had to build his own access door in the rear of the garage. In the event, this wasn’t large enough to remove his existing, temporary tanks whole, so he tried to break them up. After several unsuccessful attempts he resorted to using cheese wire to slice through the silicone of these old tanks, removing them piece by piece.

Water was being added in mid-March. Although the tank is only 2,200 l/484 gal, the attached sumps and a separate water change chamber boosts overall volume to around 3,000 l/660 gal – that’s three tons of water!

Filtration is surprisingly basic. Stuart believes in good quality live rock and a big protein skimmer, and has both. A huge Deltec SC3070S resides in the sump, a model normally suited to a 5,000 l/1100 gal system. It is enhanced by fluidised beds of Nutri-fix media and the combination maintains water quality.

Other gadgets include a huge calcium reactor, and more fluidised systems brimming with Rowaphos. Water flow is taken care of by a network of piping now completely grown over with encrusting algae, as well as opportunistic star polyps that adore the flow provided.



Darting headlong

Circulation is provided by numerous 17,000 lph Abyzz pumps, each digitally controlled, and some working in tandem or opposition to each other to create surges. When the pumps fire up the change in movement is noticeable, with fish being flung sideways and darting headlong into the powerful flows. The large tangs, in particular, clearly enjoy flitting through these currents.

Water changes are simple enough. Stuart simply closes off a 600 l/132 gal tub from the rest of the system, drains away the water, and allows it to refill with the RO supply that usually accounts for evaporation via a float valve.

Once the tub is filled, he only has to add the salt — a bucketful to be precise — and once it has had adequate time to mix he can reintroduce the tub to the rest of the system, gradually filling it with the cleaner supply.

Normally, Stuart runs a vodka-fuelled nitrate-reducing filter on the sump that houses the coral frags, but this was out of action on my visit, although the peristaltic pumps attached were still doing their thing.

The tank may as well have its own miniature sun, such is the intensity of lighting, and there are 16 x 54w and 16 x 39w T5 fluorescents within two matrix systems, as well as another three 400w Giesemann metal halides. The latter provide a compliment of white light and, running lengthwise across the middle of the tank, they are each staggered to come on for a three-hour period, crossing over at hourly intervals — moving a path of light over the aquarium.

The viewer’s perception of colours in the tank changes the more you look at it. The room has no natural light sources and the eye seems to create its own white balance, dulling some of the colours in a way you fail to notice until you leave the room for a while and re-enter.

I was most impressed by the care taken to aesthetically blend the tank into the room. The front fascia has been surrounded, professionally, to look more akin to a plasma TV screen rather than an aquarium. That’s not to say it has buttons and lights, but it is smart, and creates the uncanny illusion that you could be watching a live, high-definition documentary filmed on some distant reef. It really does transport you there.



How about maintenance?

Stuart likes to perform a monthly water change of some 600 l/132 gal at a time. This may sound a lot, but only accounts for one-fifth of the whole volume of the system. The nitrate filters do a grand job of keeping readings low and in keeping glass and substrate tip-top Stuart dedicates no more that two hours each week to maintenance.

He has no need for fiddly dosage with endless bottles of coral additives. The only supplementary chemical added to the tank is the occasional dose of iodine. Other elements are taken care of in the D-D salt mixture.

How much would your dream cost?
A tank of this majesty doesn’t come cheap. When considered as a whole, including custom built Deltec aquarium and frame, pumps, lighting, and filtration then the price begins to creep into the region of £25,000 to £35,000. It’s certainly not a light-hearted commitment.

Stuart has lost track of the value of his fish, mainly as some have been traded, swapped and simply reared on from much smaller sizes. However, given the huge groups of anthias — no less than five species reside here — and the selection of striking tangs, angels, wrasse and chromis, it’s safe to assume that his outlay on fishes is more than I’ll manage for some time.

By comparison, the inverts have cost Stuart near to nothing, as he raised all the small polyp stony corals himself from frags. This magnificent reef would have cost a paltry sum to fill, although it required patience to make it what it is.

What’s in Stuart’s tank?

Soft corals:
Clavularia — clove polyps, green and brown species.
Pachyclavularia — green star polyps
Anthelia — waving hand coral
Xenia — pulse coral
Briareum — corky sea fingers
Unknown sea whip — courtesy of David Saxby’s tank
Various zoanthids — range of colours
Yellow polyps

Hard corals SPS:
Pocillopora damicornis — pink
Stylophora pistillata — bright pink
Seriatopora hystrix — pink with blue polyps
Seriatopora caliendrum — blue birds nest
Acropora species — in multiple colours and sizes
Acropora millepora — multiple colours and sizes
Acropora granulosa — bottle brush acropora, large central coral
Montipora digitata — in red and green
Montipora capricornis — red
Montipora species — red, brown, green, purple
Porites nigrescens — green
Porites — general
Pavona — cactus coral
Fungia — disc coral
Galaxea astreata — galaxy coral
Oxypora — chalice coral
Hydnophora
Turbinaria reniformis — scroll coral

Hard corals LPS:
Blastomussa — two or three different species
Lobophyllia — orange and green species
Caulastrea — trumpet coral, green/blue
Favia species — moon coral various colours
Platygyra species — brain coral
Goniastrea palauencis — unusual honeycomb coral
Trachyphyllia geoffroyi — red open brain coral
Catalaphyllia jardinei — elegance coral
Euphyllia parancora — branching hammer coral
Duncanopsammia axifuga — Duncan coral
Acan — couple of species

Others:
Bubble tip anemone
Large Derasa clam

Fish:
Four Yellow tangs
One Purple tang
One Powder blue
One Yellow eye tang
Two Blue chromis
20 Green chromis
Ten female Squamipinnis anthias (four males)
12 female Diamondhead anthias (two males)
Three female Lori’s anthias
Three female Tuka anthias
Ten Resplendent goldie anthias
One Fathead anthias
One Copperband
One Sixline wrasse
One Iridis wrasse
Pair of Cleaner wrasse
Pair of Sebae clownfish
One multibar angel
One Bellus angel
One Bicolour blenny
One Spotted mandarin
One Foxface rabbitfish

At least a couple of Mantis shrimps that are sometimes heard clicking away…

You can see a short video of Stuart's aquarium below:

 

Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.