Your tanks: Jack Allen


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A childhood fascination with marine fish has culminated in a magnificent reef display full of movement and colour.


Jack Allen’s reef is a real spectacle and credit to Jack’s passion for all things marine.

Despite being in the kitchen, some 10m or so away from the front door, the tank and its colours are so impressive that its the first thing you notice when you step into Jack’s London home. It takes your eyes a good few seconds to adjust to the visual intensity and almost overwhelming technicolour feast, especially if, like me, you’re used to the calm and mellow green, brown and occasional reds of a planted aquarium aquascape!

This set-up was quite the opposite — much higher impact and perhaps less relaxing for some tastes, but hugely impressive nonetheless.

Early fascination

Jack started off in the hobby as a child, his father owning an aquatics business in the 1980s. He dealt mainly with koi, freshwater tropical fish and aquatic plants, but also dabbled in marines.

It was during a visit to an aquatic shop when Jack, then just eight years old, saw his first marine fish and he soon became hooked on their exquisite colours. From this young age, he kept a few basic marine set-ups, with varying degrees of success.

His dad was also a keen diver and Jack followed suit at as a young teenager. He’s since dived all over the world, which has only served to further his self-confessed obsession with anything marine related.

It wasn’t until 2008 that Jack decided to take the plunge fully as a dedicated reefkeeper. His current aquarium was bought two years ago.

Jack ordered a Seabray custom-built 12mm glass tank through H2O Aquatics and had it built on-site in his kitchen.

Measuring 180 x 90 x 60cm/6 x 3 x 2ft with a black background, black silicone and gloss black cabinet, the whole system complements Jack’s kitchen perfectly.

Bringing the aquarium to life

The fish remain Jack’s favourite part of the reef hobby. He says: "It’s the corals that provide the backdrop to the picture, but it’s the fish that bring the picture to life."

This philosophy is certainly apparent in his reef — the amount of activity is incredible. His aquarium is home to around 30 beautiful fish — wrasse, clownfish, anthias and a mixture of tangs and angelfish, with Jack’s favourite being the latter two.

The fish are fed twice a day with a large variety of flake and Gamma frozen foods including Mysis, brine shrimp, red plankton, mussel and krill. He also feeds New Era and Ocean Nutrition flakes and pellets, as well as nori seaweed.

The corals aren’t fed separately, as Jack hasn’t witnessed any noticeable improvements after trying various types of coral food.

Turnaround in coral health

Jack’s biggest problem with his set-up happened last summer when he was having trouble with his Montipora plating corals turning pale and stripping their outer layers. He also witnessed some Acropora doing the same thing. Fellow reefkeepers mentioned a theory that pollen present in the air during the summer could be poisoning the corals. Jack plodded on until autumn, when he came home one day to see a considerable number of corals stripping.

Advised by a couple of specialist marine retailers that it could be an iodine issue, Jack had his levels tested. Sure enough, they were too low, even though he was supplementing iodine twice a week. He began dosing five drops per day of an iodine supplement and said the turnaround in coral health was incredible.

Jack’s theory was that a switch from a FM Balling Lite system to a calcium reactor, with the consequential increase in demand for iodine, combined with a lack of dosing it, led to the issues.

Jack is such a big fan of his DaStaCo calcium reactor that he recommends it to anyone who is serious about growing small polyp stony (SPS) corals; this maintains ideal calcium and KH levels. He relies on good old regular water changes with RO water and D&D salt to maintain all the other parameters. He confesses to rarely testing the water and is against the principle of constantly testing for individual water parameters and the consequential number chasing.

Jack’s using T5 lamps on his set-up — 12 of them at 80W each. They were clearly doing their job; the colour rendition was amazing but the residual heat was significant. He says he has considered switching to LEDs, using three or four Hydra 52 units.

Not such angels…

Despite an invertebrate selection dominated by small polyp stony (SPS) and large polyp stony (LPS) corals, Jack has experienced little trouble with his angelfish, which are well known for taking a fancy to some LPS species.

The only exception was when his Blueface and Emperor angelfish suddenly decided to eat six large Tridacna maxima clams, despite not previously having shown any interest in them for over two years.

"This hobby constantly tests us and keeps us on our toes," he says. "Anyone with a successful marine aquarium clearly likes a challenge!"

Tank factfile

Tank: Seabray custom-built 180 x 90 x 60cm/6 x 3 x 2ft, 1,000 l/222 gal with sump (150 l/33 gal) and remote algae refugium (100 l/22 gal).

Filtration and water movement: 60kg live rock, 4 x Vortech MP40 powerheads, Bubble King Supermarin 250 protein skimmer, Twin D&D 5000 return pumps, filter floss weir in sump, two RowaPhos phosphate reactors, one RowaCarbon reactor, D&D 39W UV and remote algae refugium.

Lighting: Two ATI Sunpower T5 units (6 x 80W each) with 6 x Narva Blue, 2 x ATI Coral Lights, 2 x ATI Aquablue Special and 2 x KZ Fiji Purple. The

algae refugium has 6 x 39W T5 6,500K lamps.

Heating/cooling: AquaMedic 500W titanium heater with Tunze temperature controller and D&D chiller for summer months. Temperature is at 26°C/79°F.

Supplementation: Carbonates and calcium via DaStaCo 1,000 l/222 gal calcium reactor. Iodine dosed daily.

Total cost of system: Approximately £10,000.

Jack’s maintenance plan

Daily: Check over all of the equipment inside the cabinet, feed fish and add five drops of iodine supplement.

Twice per week: Clean the glass and empty any protein skimmer waste.

Weekly: 80 l/18 gal water change with D&D salt. Scrape the back of the aquarium, wipe skimmer cup with filter floss, replace filter floss in filter area and fill auto top-up after water change.

Fortnightly: Replace carbon in the reactor (500ml).

Monthly: Change DI resin in RO unit. Completely clean the skimmer self-clean head, top up the calcium reactor media, harvest excess algae from the remote refugium and algae bed maintenance.

Six weekly: Change RowaPhos in the reactor (1 l).

Six monthly: Clean Vortech pumps, take apart skimmer and thoroughly clean and change RO pre-filters.

Yearly: Service return pumps and calcium reactors, change all T5 lamps and change the UV lamp.

Jack’s fish list

Three Yellow tangs, Zebrasoma flavescens

Achilles tang, Acanthurus achilles

Four Percula clownfish, Amphiprion percula

Blueface angelfish, Pomacanthus xanthometopon

Yellow tail tamarin wrasse, Anampses meleagrides

Starry blenny, Salarias ramosus

Mandarinfish, Synchiropus splendidus

Purple tang, Zebrasoma xanthurum

Blonde Naso tang, Naso lituratus

Red Sea Regal angelfish, Pygoplites diacanthus

Blue spotted tamarin wrasse, Anampses caeruleopunctatus

Royal gramma, Gramma loreto

Spotted mandarinfish, Synchiropus picturatus

Powder blue tang, Acanthurus leucosternon

Regal tang, Paracanthurus hepatus

Emperor angelfish, Pomacanthus imperator

Six Common anthias, Pseudanthias squamipinnis

Leopard wrasse, Macropharyngodon bipartitus

Firefish, Nemateleotris magnifica

Meet the aquarist

Fishkeeper: Jack Allen.

Age: 36.

Profession: Self-employed restaurant owner and luxury car dealer.

Time in hobby: 30 years.

First fish: Green tench.

First breeding success: Siamese fighting fish.

Number of tanks: One.

Favourite fish: Emperor angelfish.

Fish he’d most like to keep: Reef shark (in a suitably large aquarium).