How do I control this grass-like algae?

Dave Wolfenden offers advice for a reader who's having a turf war in his reef tank.
Q. I was wondering you might be able to offer some help with controlling an algae outbreak in my aquarium. The algae seems to grow from the coraline algae and is a very dark green, wiry and hard grass-like algae. It requires a bit of force to remove it.
My parameters are: NH3 nil, N02 nil, N03 <5ppm, Phosphate nil, pH 8, KH 10°, calcium 420ppm, sg. 1.026, temperature 25°C/77°F — done using API tests except pH (Salifert).
Lighting is TMC AquaBeams with white and blue LEDS mixed on each strip, controlled at 70-75% with the TMC controller. Lights are on fade from 10am till 12noon, on fully til 6pm and fade off by 8pm.
For filtration I'm running two powerheads, V2 400 skimmer, Fluval 306 with just Rowaphos and Purigen which is replaced monthly. The tank is 125 l/27 gal and has 25% water changes weekly.
Stock is a False clown, Yellow goby, Sixline wrasse, Coral beauty, two Yellow-tailed blue damsels and a Red Scooter Blenny, along with a green Bubble anemone, a Knobbly toadstool coral, Jasmine coral, plus colonies of Zoanthus and Blue mushrooms, two feather dusters, hermits, Turbos and a Cleaner shrimp. There’s 12kg of live rock in the tank.
The issue probably began way over a year ago when I was running standard fluorescent bulbs. But now I'm considering a larger upgrade so I would like to figure a way of controlling it or beating it if possible. Can you help?
Andy, email
A. From your description, I’d suggest that this might be a species of Cladophora, which also answers to the name of 'brush alga'. It’s quite tough stuff, and as you’ve discovered it’s pretty resilient too. It commonly ‘hitch hikes’ on live rock, and can appear many months after the rock is introduced. There are two approaches to controlling algae — limiting nutrient input and removal — either manually or through biological agents.
Manual removal can help to an extent, but the algae will simply grow back. Not many herbivores touch these wiry algae, and your choice is limited anyway due to the size of your system and its existing inhabitants. A tang isn’t an option as even a small specimen needs much more room. An Emerald crab (Mithraculus sculptus) might eat it, but these can be quite aggressive and cause their own problems.
On balance, I’d suggest that you concentrate on limiting nutrients, specifically nitrate and phosphate, to put the squeeze on this unwanted visitor. Although your readings for both phosphate and nitrate look fine, here’s the thing: there may be unacceptable amounts of these algal fertilisers being generated in the system, but the algae is actually assimilating them, meaning they are not being detected by your test kit.
Review feed input to the system, and make sure that excess food is not being added. Washing frozen feeds to get rid of residue can be useful to limit nutrient input. Ensure that the skimmer is functioning optimally, and give the tank’s substrate a really good clean on a regular basis.
Although you’re already performing 25% water changes weekly, I’d suggest increasing the frequency of these to twice a week, and if you’re not already using RO water, then seriously consider it.
It might be worth thinking about upping the tank’s mechanical filtration, and — if it’s not the case already — part of your external filter could incorporate a mechanical sponge, which should be frequently rinsed in tap water to prevent build up of detritus, and to stop the media from becoming a biological filter (which may contribute to high nitrate levels).
Algal issues arise due to an excess of nutrients, and by reducing the input of these (and ensuring their swift removal from the system) it is possible to curb the problem — in time...
Dave Wolfenden
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How do I set up a Red Sea biotope aquarium?

Dave Woldenden has some advice for a reefkeeper who's been inspired by a recent holiday.
Q. A recent holiday to the Red Sea has inspired me to set up an aquarium hosting corals and fish from that area. I have some experience of keeping marine fish and invertebrates, and plan on using a 580 l/128 gal tank. What can you suggest as suitable inhabitants?
Ray Burns, Portsmouth
A. This sounds like a great idea for a themed aquarium, and there are plenty of possibilities. Lots of fish and invertebrates in the trade occur in the Red Sea, although obtaining specifically endemic species could be pretty expensive, and you’ll need some luck getting hold of some of the more specialised animals.
For me, the quintessential Red Sea fish would be the readily-available wreckfish Pseudanthias squamipinnis, and I’d base a biotope around this fish if you’re after a really authentic Red Sea look — you’ll certainly have enough room for a great aquascape.
Instead of constructing a wall of rock at the back of the tank, I’d create a fairly extensive sand zone, with substrates varying from fine sand to larger chunks of rubble. Dominating the sand zone, I’d build up a live rock coral 'head' (or 'bommie') – some creative use of cable ties, PVC pipes and epoxy resin can yield something more interesting than a mere stack of rocks.

This hardscaping can form the focal point of the system, and may be used to house, for example SPS corals such as Bird’s nest coral (Seriatopora hystrix) and Cauliflower coral (Pocillopora verrucosa), both of which are common in the Red Sea. These are quite demanding, however, and as an alternative soft corals such as pulsing Heteroxenia fuscescens (pictured above by Derek Keats, Creative Commons), Anthelia or Sarcophyton might be more to your liking — as well as being more forgiving.
You could keep a shoal of six or so wreckfish, but make sure the group contains only one male (sexing is easy, with males having an elongated third dorsal fin ray and a more intense purple coloration). Other fish of note include the Orchid dottyback (Pseudochromis fridmani), a Red Sea endemic, and Purple tang (Zebrasoma xanthurum).

If you’re interested in clownfish, then you’d really have to look at seeking out a pair of the endemic Red Sea clownfish (Amphiprion bicinctus) and if you can maintain optimal water quality, a Bubble tip anemone (Entacmaea quadricolor) placed on the coral head would provide an ideal home.
There are plenty of other possibilities, but that’s my suggestion. Personally, I think it’s an opportunity to create something really different, and rather than go crazy with a 'pick and mix' approach, judicious selection of a few species will yield results. As they say, sometimes less is more...
Dave Wolfenden
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How do I stop flatworms eating my Acropora?

Levi Major advises on how to get rid of those coral-eating pests.
If you have seen coral-eating flatworms, I would recommend treating the affected coral in isolation, in the hope that the infection has not spread to other corals. You could attempt to cure the outbreak with wrasses from the Halichoeres or Psuedocheilinus genera, but I believe these will only keep the problem at bay.
Your best bet for a complete cure would be to quarantine your corals and undertake dips. While freshwater dips could work, these are not the best option for SPS and should be limited to a maximum of 30 seconds in water closely matching the temperature and pH of the aquarium.
Better would be an iodine-based dip following the manufacturer’s recommendations.
As flatworms get deep into nooks and crannies within the coral, treatment may necessitate a small powerhead in the dip water to help wash them out.
Failing that, a gentle swish can help dislodge the more stubborn worms.

copyright © Dr Kate Rawlinson
Several dips over several weeks may be needed to fully eradicate them. It should, however, be noted that most treatments will not deal with any egg sacs.
Attacked corals tend to show tissue recession from their base where you will see many little brown eggs. These can either be scraped off during dips, or any dead areas of the corals can be cut away to leave healthy tissue and any emergent flatworms dealt with during subsequent dips.
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How do I breed Longnosed hawkfish?

Fancy a challenge? Expert marine fish breeder Matt Pedersen takes a look at spawning the Longnosed hawkfish in the aquarium — and the first part of that challenge is trying to get a pair!
I understand that while the Longnosed hawkfish (Oxycirrhites typus) has been spawned in captivity, it has not yet been successfully reared to juvenile stage.
Current knowledge suggests that all hawkfish are protogynous hermaphrodites, meaning they start life as female and the terminal sex is male. Most marine aquarists are more familiar with this lifestyle in wrasse and anthias. In fact, much like these families, some Hawkfish are thought to live in harems.
I once tried to pair the Longnosed hawkfish, but it did not go well! I selected two 5cm/2” specimens and placed them together in a tank. They immediately began to circle, trying to attack each other. After 20 minutes trying to separate them, we realised this wasn't going to work.
I've had similar experiences when trying to pair two small specimens of Bicolor angelfish. It seems that the problems stem from each fish's desire to be boss and since they are the same size and equally matched, neither backs down.
Successful pairing of hawkfish seems more likely to occur when there’s a noticeable size difference between mates, which might mean looking for the smallest specimen you can and then a second at least 1-2cm/0.4-0.8” larger.
Starting with large hawkfish is to be discouraged. You increase your chances of having two males and we don't know that hawkfish can revert to being female.
Ideally, you want the smaller fish to realise there's no chance of being dominant, so minimising aggression. Still, it would be wise to introduce them in a way they cannot initially cause physical harm, such as housing the smaller specimen in a clear container for the first week.
Once you have a compatible pair, conditioning them to spawn simply involves heavy feeding with quality foods. Having your lights timed helps the fish get in tune with day-night rhythms and, in time, they should do what comes naturally.
Hawkfish are pelagic spawners that make a spawning rise, so have a well fitting lid on the spawning tank. This also means the fish may need considerable vertical height to spawn successfully. For this reason, some breeders of pelagic spawning fish prefer vertical barrels as broodstock aquariums.
Beyond that, there are no specifics. You'll have to collect the eggs, incubate and hatch them, and figure out how to rear them yourself!
Mandarins (Synchiropus sp.), dwarf angelfish (Centropyge sp.) and the Harlequin filefish (Oxymonacanthus longirostris) may have similar starting points and could provide the tools needed to get the job done.
How do I breed my Peppermint shrimps?

For a marine shrimp, the Peppermint shrimp is relatively easy to breed. Matt Pedersen has a few tips.
April Kirkendoll’s book How to Raise and Train Your Peppermint Shrimp (ISBN 978-0-966-7784-4-1) will tell you everything you need to know. My advice, first and foremost, is to read it from cover to cover!
One of the big plus points of Peppermint shrimp rearing is that it’s reportedly ‘very easy’. I haven’t seriously attempted to do so yet, but they’re on my list!
The shrimp mate only hours after moulting and they are simultaneous hermaphrodites, meaning all you need is a pair of any two random individuals. If healthy, they will mate.
Mating is the easiest part of the process. Single individuals may even produce eggs after every moult, but, lacking a mate for fertilisation, these will not hatch.
One of the most difficult things may be actually getting the babies. The baby shrimp hatch after lights out, shortly before the adult moults again. Serious rearing would utilise dedicated tank space and this would reduce predation on the larvae as they hatch.
Typically, larval collection involves turning off the filtration the night of a hatch and using a device called a ‘larval snagger’ to collect the larvae. After collection is complete, you can transfer the larval Peppermint shrimp to a rearing container and fire up the filters once more.
Peppermint shrimp rearing is ‘easy’ because they only require baby brineshrimp as a first food. It is important, however, to enrich baby brine with a HUFA enrichment product like Super Selcon or to use phytoplankton.
Another reason for ‘ease’ of breeding is that typically no special larval tank is required. A standard 37 l/ 8 gal glass tank with heater and air feed for circulation should do the trick. You may need to black out the sides and bottom of the tank and cover the light on the header to prevent the babies congregating there.
When things go right typical settlement occurs about 35 days post hatch, but can take longer.
This is a very short answer, but this species is well documented, so do read up. Note that multiple species of Peppermint shrimp enter the hobby and not all are equally easy to rear.
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Can I keep a group of Common clownfish together?
Is it possible to keep clownfish in social groups in the marine aquarium? Matt Pedersen advises.
In the wild, many clownfish live in social groups of a dominant female, a male, and one or more subordinate sexually immature male juveniles. Social pressure keeps the younger ones, not part of the pair, from maturing. They patiently wait their turn.
Images of clownfish in the wild reveal many species in groups, including Saddlebacks (A. polymnus), Common (A. ocellaris), Percula (A. percula), Black-footed (A. nigripes), Clark’s (A. clarkii), Pink skunk (A. perideriaon), and, I’m sure, others.
You may find big colonies of clownfish among large aggregations of anemones, with multiple pairs sharing adjacent spaces. However, I would never expect a group of a certain species to work, most notably the Maroon clown (Premnas biaculeatus).
Replicating the ‘pair plus’ social group in captivity doesn’t always work, but I’ve seen it work with ocellaris and clarkii, as well as having seen a massive group of Pink skunk (Amphiprion perideriaon) at Atlantis Marine World in Long Island, USA.
That doesn’t mean it will always work with these species. There is definite merit in adding all the fish at the same time as juveniles. If I tried adding a juvenile percula or ocellaris to a tank with a spawning pair, though, it would quickly killed.
Starting with juveniles all at the same time has risks and in more aggressive species may fail to work. I have a small isolated group of five black ocellaris (Amphiprion ocellaris ‘Darwin’) which are all siblings — the larger two being hatched a batch earlier. Even at three months, social pressure has created a runt that takes the brunt of aggression, so it hides, only showing up to feed.
I suspect that if I removed this fish the next one would suffer, and so forth, ultimately leaving me with just a pair.
In nature, clownfish living in groups will breed. In captivity it's generally felt that if you have more than two in a group breeding will be delayed because the fish will spend more time determining social rank. You may reduce the chances of this happening by selecting a larger, medium and one or more small fish — all from a group of juveniles.
Because size tends to correlate to social status and sexual function, judicious selection of fish may help reinforce the natural rankings each fish should occupy.
These fish may or may not breed. Things may go well for a while, but then, as the dominant pair matures, they may attempt to drive off all other fish. This may result in deaths, or a second splinter group which then forms its own breeding pair.
How all of this may occur depends on tank size, hosts and personalities. It is impossible to predict outcomes, so have spare tanks or breeder nets ready to isolate all extra fish if cohabitation doesn’t work!
Why have my clownfish suddenly stopped spawning?
If your clownfish have been breeding regularly and then suddenly stop, could it be a sign of ill health? Matt Pedersen looks at the possible reasons for them going on strike.
In the wild some clownfish species have breeding seasons and these are thought more likely in those in more temperate/subtropical locations. Wild spawning may also be tied to lunar rhythms.
In captivity it is not uncommon for clownfish to 'go on strike' and stop breeding. Sometimes they will resume, sometimes they won’t. There is no single answer, but here are some possible solutions.
Making a change or disrupting the broodstock aquarium can stop them in their tracks. Rearranging the tank’s décor could be enough. Adding new fish to the tank could also potentially throw them, especially if conflict results.
Several clownfish varieties and species are typically thought of as unreliable spawners. Amphiprion ocellaris are generally not lumped in that category, but for people with fish like skunk species, including Amphiprion perideriaon, A. sandaracinos, A. nigripes and others, sporadic spawning is almost considered the norm!
As for 'seasonal' breeding, you may have inadvertently given them a cue to stop spawning. A drop in tank temperature could easily slow or stop them. All my tanks run cooler in the winter and spawning behaviour adjusts.
Shortening your lighting cycle could also be an environmental cue to stop spawning.
Other possibilities may include old age, although clownfish can live up to 30 years and I know of at least one 21-year-old pair of Tomato clownfish that still spawn routinely!
Look at their general health and condition. Low feeding levels may have caused them to stop to restore depleted reserves of nutrients required. Actual disease, parasite, virus or bacteria can also stop fish from breeding.
Any one factor could be your problem, so check and rectify. If this doesn’t work be patient, for in clownfish breeding time is the one thing we can’t substitute!
How do I enrich baby brine shrimp to feed my baby clowns?

So your clownfish have bred and the eggs are looking about ready to hatch. Marine expert Matt Pedersen has some advice on feeding the babies, and on enriching baby brine shrimp for marine fish fry.
In truth, the gut loading of baby brine shrimp (aka. Artemia nauplii) may not be necessary for baby clowns, but it certainly won't hurt. The reality is that some baby clownfish can be weaned straight from enriched rotifers to rotifer-sized larval feeds such as Otohime A. I've personally introduced such larval feeds as early as 4-5 days post hatch, while maintaining rotifers until the larvae are fully weaned, and in fact I've managed to rear clownfish without using brine shrimp nauplii at any stage.
I am aware that at least one commercial clownfish hatchery in the USA does not hatch baby brine shrimp for any of their clownfish. However, just because you "can" doesn't necessarily mean you "should" or that it's the best way to do it! And for other marine fish babies, you may certainly need baby brine to elicit a feeding response.
I should address why you may need to gut-load, or enrich, baby brine shrimp. The simple answer is that brine shrimp not a true "marine" species. The result is that they do not naturally have the high levels of DHA that marine species, such as Copepods, contain. Larval marine fish of all types require DHA, as well as EPA, for proper development.
When these HUFAs (Highly Unsaturated Fatty Acids) are deficient from the larval diet, the result is that babies are susceptible to shock-related deaths. This is typically referred to as SFS (Sudden Fright Syndrome), where any sudden stimuli can result in the baby fish appearing stunned, sinking to the bottom, twitching, and possibly ending with their death.
The method of bringing clownfish directly from rotifers to prepared larval diets works to prevent SFS because the prepared foods contain the required HUFAs. There is no reason you cannot offer both larval diets and baby brine shrimp together to your baby clowns.
You cannot "enrich" newly hatched brine shrimp. The first stage after hatching is known as "Instar I", and at this stage, the nauplii has no mouth. In other words, it can't eat, so it can't be gut loaded. You can "soak" this stage in a HUFA solution like Super Selcon, but at best, you're hoping that some of the enrichment solution adheres to the outside of the baby brine shrimp and is consumed by the baby fish.
You may need to start offering Instar I nauplii due to their small size – waiting to enrich the baby brine shrimp might result in a nauplii that is too large to feed on, and calorie wise, "Instar I" is superior to "Instar II". Soaking will be your only real option until the baby fish are large enough to accept the next stage.
Because Instar I does not feed, you have to wait for the baby brine shrimp to grow and molt, entering Instar II. Indeed, it will be about 12 hours after hatching to reach this stage. At this point, the baby brine shrimp can take up enrichments like Super Selcon or phytoplankton (you can use live phytoplankton or any number of prepared phytoplankton products).
The actual length of time needed to enrich varies depending on which author you reference. Given that brine shrimp do not always hatch in unison, the best approach would be to add enrichments six hours after hatching, and harvesting the nauplii for use somewhere around 14-16 hours after hatching. You may also wish to refer to the manufacturer's own instructions for enriching with their particular product.
The bottom line is that for baby marine fish, brine shrimp nauplii are a somewhat inferior food. The use of copepod nauplii when possible would be much more beneficial (and in some cases it is known to be required), although it is much more complicated and intensive to provide at this time. Thankfully clownfish are "forgiving", and baby brine shrimp need only represent a week or two of larval feeding at most.
For more information on working with the myriad of plankton utilised in marine fish culture, I strongly suggest tracking down a copy of the "Plankton Culture Manual" by Frank Hoff of Florida Aqua Farms. This book is currently in its 6th edition.
Check out Matt Pedersen's other marine fish breeding q and a's on this website:
How do I get started in breeding marine fish?

Want to breed marine fish, but don't know where to start? Matt Pedersen offers a few tips.
Start by keeping more than one fish of the same species! Ten to 20 years ago, putting something like two Pygmy angelfish of the same species in the same tank would have been shocking.
While not advocating haphazard additions, aquarists have learned more about social and reproductive strategies of fish, so the concept of one per tank is now antiquated.
Many reef fishes we keep can be spawned readily in a regular aquarium and heavy feeding and a clean environment often get mature fish spawning.
Beyond needing broodstock, you will need at least one or two extra aquariums for larval rearing. You’ll also need to establish cultures of live foods, typically including rotifers and phytoplanton as base feeds.
Too often hobbyists wait until their fish start breeding before establishing food culture and have to scramble. Start learning and culturing before you actually need them.
If seriously interested in breeding, research your preferred species. You may also find the information necessary to pair them up.
Among the best beginner fish are Banggai cardinals, some clownfish, seahorses with benthic larvae, Bristletail filefish, Green wolf eels, Convict eel goby/blennies, Neon gobies and some dottybacks. These have very manageable rearing protocols and have short or no pelagic larval phase.
Research with books, magazines and online. Planning ahead is the best advice I can give — that and be willing to withstand failures as it’s not often you get it right first time!
This item first appeared in the December 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
Do corals need to be acclimatised before I add them?

How should we acclimatise newly purchased corals? Jake Adams advises.
Corals do not normally need acclimatisation in the same way as fish and higher invertebrates.
Fish, crustaceans and molluscs have closed circulatory systems which aim to maintain an internal chemistry ideal for their biological needs. Their biochemistry is affected by the outside environment and they can be adversely impacted upon by rapid changes in temperature, salinity and pH; hence the need to gradually acclimatise fish and motile invertebrates when transferring them from one environment to another — especially when they are undergoing shipment.
Corals and other cnidarians have no circulatory system in itself and they pretty much let it all hang loose. Coral tissues are fairly permeable to the outside environment so are less sensitive to small changes in salinity, pH or temperature.
Although corals may not usually require formal acclimatisation, when long-term transport is concerned observe newly-shipped corals. They will likely appreciate extra water flow when first added to a new aquarium to help them shed mucus and recover better from that stress of transit.
This article was first published in the December 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
Can I raise Banggai cardinal fry artificially?

When it comes to breeding marine fish, Banggai cardinalfish are one of the easiest. But what happens if your male is a less than perfect father? Matt Pedersen looks at artificially hatching those eggs and fry.
You can raise your Banggai fry artificially, but successes to date have been limited. Air-driven egg tumblers, as used to rear the eggs of mouthbrooding cichlids, have failed to yield satisfactory results. Tumblers driven by adjustable water flows seem to work better.
Eggs tend to die and decay in artificial incubation and antibiotics may help. With incubation periods of 21-27 days, dependant on temperature, observations have shown that eggs collected after one or two weeks are more likely to withstand artificial incubation than those harvested immediately after spawning.
Natural incubation is best, but not every male is a perfect father and the ability to artificially incubate Banggai eggs has commercial implications. The less time a male has to spend incubating eggs, the more frequently he can be brought into condition and spawned.
With better artificial incubation methods, theoretically Banggai production numbers could be substantially increased.
Many have tried to feed juveniles prepared foods, but most breeders find there is no artificial or prepared substitute for first foods. You can’t simply feed the babies crushed flake foods as you might with the fry of some African cichlids.
Baby Banggais appear to need prey movement to stimulate feeding. Baby brineshrimp make an acceptable first food, as do some copepods. HUFA supplementation is necessary with baby brineshrimp until prepared foods such as minced Mysis shrimp and Cyclop-Eeze are accepted.
This article was first published in the December 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
How do I breed Mandarins?

Dragonettes offer a great challenge for the marine fish breeder. Matt Pedersen has some advice to help you succeed.
Dragonettes of the genus Synchiropus are being spawned more frequently. I have spawned and attempted to rear the four most common species in the trade — S. splendidus, S. picturatus, S. ocellatus, and S. stellatus — and all exhibit sexual dimorphism and/or dichromatism and the first dorsal fins vary in structure, size, shape and sometimes coloration.
Male S. splendidus and S. picturatus have an elongated first dorsal ray, provided it has not been damaged. Male S. ocellatus and S. stellatus have large, sail-like dorsal fins with scrawling and ocelli. Females have short black dorsal fins, sometimes edged in white.
Dragonettes pair easily. Select a male larger than the female and healthy, well fed pairs rarely quarrel. They require frequent daily feeds of quality frozen and prepared foods to attain spawning condition.
Those not trained on to prepared food, but left to fend for themselves are unlikely to ever come into spawning condition. All too often this simply leads to long-term starvation.
Taller tanks facilitate a rise in spawning and some breeders have cited short tanks as a possible cause of fertilisation problems. Synchiropus have been spawned in 45 l/10 gal tanks, but larger is recommended.
Pairs court and spawn around dusk, rising to the surface and releasing 50 to several hundred floating eggs. These can be skimmed from the surface, incubated separately and will hatch in 12 to 16 hours. Two to three days later larvae have developed eyes, mouths and gut, and start feeding.
Greenwater technique with rotifers has provided random successes as first foods, occasionally resulting in a couple of larvae per batch. Success improves when introducing copepod nauplii to the diet, as well as stringent enrichment protocols.
Around two to three weeks, Synchiropus larvae settle to the bottom and start feeding on benthic fauna. Here too, copepods may play a vital role in early survival success. Brineshrimp nauplii are also taken. Over the next few weeks, the juveniles can be weaned onto prepared foods like crushed pellet foods.
It can take over a year for the juveniles to reach a marketable size.
This item was first published in the December 2009 issue of Practical Fishkeeping. It may not be reproduced without written permission.
Why can't I keep Blue starfish?

If attempts at keeping these lovely starfish in your reef tank end in failure, what could be the cause? Nick Jones has some advice.
Blue Linkia sea stars can suffer for several reasons. Firstly if your star isn’t lasting more than a few weeks it’s probably due to incorrect acclimation. All echinoderms are extremely sensitive to changes in salinity and require a long dripping off process to get the water it arrives in to the same salinity to your aquarium, this can take up to as long as five or more hours. If your star begins to lose legs or fall apart this is sure sign of salinity shock.
Linkia require a lot of rockwork to survive long term, at least 100 kilos per star. No one is exactly sure what they eat but they get their nutrition from something on the rocks themselves, possibly bacteria or detritus, but whatever it is it’s the amount of live rock that keeps them alive.
This item was first published in the November 2009 issue of Practical Fishkeeping. It may not be reproduced without written permission.
Can I keep a Harlequin shrimp?

They're lovely to look at, but Harlequin shrimp have one rather large downside, as Will Messenger explains.
Harlequin shrimp make beautiful and fascinating aquarium subjects but have a special dietary requirement – sea stars.
Often used to control nuisance Asterina stars in a reef, these incredibly marked shrimp will starve and die once these small stars run out.
The only way of keeping Harlequins long term is to provide other sea stars such as Fromia or Linkia species for them to eat instead. This can be costly and if you like your sea stars to live, it might be a heart wrenching experience as the shrimp are likely to need at least one star per week.
This item was first published in the November 2009 issue of Practical Fishkeeping. It may not be reproduced without written permission.
Why don't my Peppermint shrimp eat Aiptasia?

Peppermint shrimps are often sold as a natural control for Aiptasia. Will Messenger explains why they don't always do a good job.
This is a common problem people find with Peppermints. They are sold what as look like the desired species, Lysmata wurdemanni but in fact are another species – often Lysmata californica or Lysmata boggessi which are very similar.
True Peppermints have a red tail and red stripes down the body, whereas many of the other species have black or blue tails with silver stripes surrounding the red stripes; sometimes it’s not easy to tell, but a good book with pictures of some of the different species will go a long way to helping you select the real thing.
Saying that, even true Peppermints sometimes won’t eat very large Aiptasia, in which case manual intervention with a syringe and an Aiptasia-killing product to remove the very large ones might be necessary.
This article was first published in the November 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
Is coralline algae beneficial?

Coralline algae growth is a good indicator that your reef tank is suitable for corals - but can you have too much? Jake Adams advises.
Coralline algae is a part of the reef which I would argue has a neutral place in most reef aquaria. When one is first established, the first few spots are a good indicator that the water is suitable for coral and especially stony coral growth.
A light coating on your live rock helps to prevent any other less desirable algae from taking hold and, by itself, encrusting, plating and branching, coralline algae can be very attractive.
However, should this algae really take a liking to your aquarium, its unchecked growth can cause problems. Rampant growth will cover and obstruct the inlets and drains and you will have to scrape it off all those undesirable places.
Furthermore, if aiming to keep an aquarium with a high density of fast growing stony corals, a large standing crop of coralline algae will compete with them for vital minerals and trace elements.
This item was first published in the October 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
How should I aquascape my reef tank?

Aquascaping your reef tank? Jeremy Gay offers some advice.
The traditional marine tank aquascape uses lots of live rock, piled left to right, front to back, filling the tank. Corals are then spaced out along the pile, with light-requiring species at the top and low light species at the bottom.
This design is well proven but doesn’t really represent a natural reef, uses more live rock than you need and dead spots may occur at the back, behind the rock.
A modern aquascape should be much more open for better water circulation, assembled to make interesting shapes and overhangs and also built with coral growth in mind.
Pick rocks with some interesting shapes, and those that lend themselves to becoming natural caves, bridges and rocky overhangs.
Be more adventurous with your rock placement by drilling rocks then fastening them together with cable ties. Rock can be threaded onto plastic tubes or rocks to create pillars or bommies, onto which corals can be securely attached with putty. The result is an aquascape that is much more interesting while still having a large surface area for filtration and coral placement.
Move rocks from the glass sides and back and water can flow all the way around the live rock, making it much more efficient and preventing the build-up of sediment and detritus that could harbour nitrates.
With better water flow and more rock surface exposed, less rock can be used, cutting down on weight and the amount spent on this feature. You can even use modern replica rocks, which defy gravity and jut out from other rocks, creating space for corals on top and a shady overhang for shade-loving sun corals and fish underneath.
This item was first published in the October 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
Can I use natural seawater in my aquarium?

I live near the coast and have easy access to clean salt water for free. Are there any advantages of using natural seawater?
I wouldn’t use water from our native seas as the planktonic life within it will be coldwater/temperate as opposed to tropical, though some do. You can buy boxed natural seawater, eliminating the need for mixing and measuring.
Live seawater can be purchased, boasting added extras, including bacteria for cycling and waste reduction, and plankton for feeding corals. It does cost, however, and you have to transport it home. Yet many of us have to do that with RO barrels too!
In the short period I had 'live' seawater on test I didn’t notice any benefits over synthetic or solar evaporative make-your-own salt as I already had live rock and live sand in the tank, and they too bring in bacteria and plankton.
No major breakthroughs have been made since the introduction of live seawater and the whole hobby has been problem free with saltwater you mix yourself.
This item was first published in the August 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
Why does my anemone keep walking round my tank?
Anemones can walk, and it's not unusual for them to wander round the tank. Nick Jones explains why.
Anemones can have demanding requirements as regards lighting, feeding, water flow, temperature and water quality. This may also sound necessary for many corals, but many stunning tanks full of SPS corals have struggling anemones.
Anemones can walk. They find a position they feel comfortable in and bury their foot in the sand or attach to a rock. If conditions aren’t suitable in the reef tank they will wander, looking for a more favourable position. This can lead to neighbouring corals being stung or the animal getting into an unprotected pump inlet and meet its doom.
If yours continues to move it’s because it can’t find a suitable location, the right amount of light or because water conditions aren’t exacting enough.
If your anemone doesn’t settle within a week or so, your tank may never be suitable and the best thing would be to pass it to another hobbyist whose tank is more to the animal’s liking.
Even established anemones will often move occasionally and poke out of different holes in the rocks. This isn’t something to worry about.
This article was first published in the Christmas 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.
Can I keep corals under T8 lighting?
Yes you can, if you choose your corals carefully. Jake Adams has some suggestions.
There are many conditions under which corals can be kept under T8 fluorescent lighting. Keep non-photosynthetic corals such as Tubastrea (pictured above), Balanophyllia and Dendrophyllia species which require a weekly feeding of small meaty morsels.
It is still possible to keep all species of photosynthetic corals under T8 lighting as long as we know the limits of our lighting and have realistic expectations for the rate at which corals grow under reduced lighting.
In addition to generous water flow and feeding regularly, when trying to grow corals under T8 fluorescent lighting the aquarist should seek to optimise the performance and PAR output of his or her lamps.
Warmer coloured lamps will usually emit more PAR per watt, an efficient electronic ballast should be employed to maximise lamp output, every lamp should be coupled with a reflector and, where possible, the fluorescent lamps should be as close to the water surface as possible.
Although you may not be popular for handing out SPS frags left and right, there are still plenty of corals that will live and thrive, and sometimes even look better when put under normal output fluorescent lighting.
Most zoanthids, corallimorphs and leather corals should feel at home in a moderate light reef and many LPS such as disc corals, brain corals and even Acanthastrea lordhowensis should do really well under a few banks of T8 lights.
Although keeping corals in reef tanks lit exclusively with T8 fluorescents might seem out of place today, not that long ago the best reefs were lit exclusively with less efficient T12 fluorescent lights.
This article was first published in the Christmas 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.