Home > Aquatics > Marine Aquarium Articles > Marine Fish Keeping setup and article by John W

Marine Fish Keeping setup and article by John W

I first started keeping tropical freshwater fish in 1964 and by 1980 had over 1000 gallons of water across 20 tanks in a purpose built fish house.  Following a house move and change of job we setup our first 3’ 20 gallon marine tank in 1982. By today’s standards boy was it crude and at that time equipment, usually German, was scarce and expensive.  Reliable information was difficult to obtain and much was learnt through trial and error and a very bent credit card.  
By the early 1990’s the hobby had moved forward leaps and bounds and we upgraded to a 50 gallon 4’ tank. Luxuries like UV sterilisers and a wide choice of protein skimmers were now available to make life much easier for both us and the tank’s inhabitants. As the hobby evolved over the next 10 years new ways of tank maintenance and lighting were introduced and loses became few and far between.  Caulerpra had to be thrown out in handfuls because it began to grow so fast that it threatened to choke the tank and corals were constantly being propagated off.  In fact for four years we didn’t have a single loss until in a moment of stupidity I introduced ten of the new wonder turbo snails without first placing them in quarantine.  Three months later after loosing around half the stock the tank finally became stable again.
Three years ago as we sat looking at the devastated tank we wondered do we restock or setup a bigger and better system, well we went for the latter, a 150 gallon system incorporating a 2 metre display tank with sump and minimal maintenance effort, I’d had enough of mixing up salt water, draping hose pipes across the living room and carrying buckets of water around.
The setup which we decided upon and has now been running for a ten years and is briefly as follows, the main tank sits on a home made timber base is 2000mm long, 600mm tall and 580mm wide with a weir at back centre feeding the sump. The top of the tank is open to allow maximum light penetration, illumination being provided by an Arcadia 3 series pendent.   Below the main tank to the left is a 1000mm long sump divided into three sections, to the right is a holding tank for R.O. water or saltwater storage and between them is a very compact space containing all the electrics, just!

If that hasn’t bored you already and you haven’t tuned the page then here are the details of the setup.
As I have already mentioned the main tank is 2metres long and allowing for rocks I reckon now holds about 100 gallons of water. At each side of the weir which is located rear centre and each rear corner of the tank, is a ‘Zoo Med’ oscillating power head, these four power heads are controlled by a System 2000 wave simulator module, they create random water movement in what would otherwise be quiet corners of the tank and help to push food and detritus forward, as power heads they are fine as oscillating water jets they are a waste of time, sticking when the least bit of dirt or grit manages to land in the gears requiring cleaning at least once a week to keep them moving, sorry this is supposed to be a low maintenance tank, they stuck a long time ago and can stay stuck! Originally these power heads were fitted with air injection tubes but they were so efficient at pulling in air that the main tank looked constantly cloudy with suspended small air bubbles so now they just move water and have no air intake.  Out of sight at the rear base of the tank there is a little (20kg) tufa rock for ballast on top of which is over 60kg of living rock which I consider to be the main filtration mechanism.  The bottom of the tank is covered with a thin layer of coral sand for cosmetic purposes.

Lighting is provided by a 5 foot Arcadia ‘3’ series.  This unit houses three 150 watt 14,000K metal halide lamps and two 5’ marine blue actinic tubes, unfortunately the control system for the tubes failed some years ago and Arcadia are unable to provide a replacement.  The blue tubes were timed to come on at 07.00am and remain on until 10.00pm. The halides come on at 08.00am and remain on for 12 hours until 08.00pm.  Initially this light unit was thought to be a little too short however in retrospect it has been found to be useful to have the ends of the tank not quite so brightly lit for those species of corals which prefer slightly lower light conditions. To aid general light transmission the tank has an open top.

Holding all this up is a stand made from sawn and treated 2”x4”, there are ten support legs in total with four diagonals braces to add rigidity.  Each leg is about 20” apart and is positioned to sit exactly over the floor joists  (which have themselves been given extra support).  Two 4”x4” battens run left to right at the top and two at floor level, these are fixed to treated 18mm weatherproof boards, it’s built a bit like a battleship but it does have to support around 2,000lb.  The whole construction sits on inverted carpet tiles glued to the bottom board and the tank itself sits on a polystyrene base.  The dimensions of the tank and stand are such that they are an exact multiple of standard kitchen units therefore they fit exactly inside standard kitchen cabinet size doors, which in my case were made by B&Q.  The doors and sides clip on to the stand and can all be easily removed for maintenance and cleaning.

Below the main tank and to the left sits the three compartment sump holding about 60 gallons of water, this is gravity fed from the main tank down the weir tower which contains bio balls acting as a biological filter media and first large particle trickle filter. Water arrives in the left hand chamber of the sump which houses a Deltec APF600 protein skimmer, this is fed with ozone from a Red Sea Pharm’s 100 Aquazone Plus set to 50 mg/hr of ozone with a maximum redox level of 320mV.  Output from the skimmer is passed through carbon before being returned to the chamber.  

From chamber one, water flows to the second chamber of the sump which has 24 hour lighting and contains several species of caulerpa in a bed of miracle mud, here are also two 150 watt heaters and an Eheim 1250 pump. The heaters are controlled by a Rocon Protemp proportional temperature control system, a brilliant piece of kit which I believe is no longer marketed.  The output of the Eheim is connected to the domestic waste water system and is manually switched on but timed to switch off when a measured amount of water equal to that of the holding tank has been flushed from the sump, this enables easy partial water changes.     
From chamber two the water flows through a second finer trickle filter and carbon into chamber three.  Within the third chamber there is rapid aeration and two further pumps, the first an Eheim 1264 returns the bulk of the water to the main tank at the rate of around 4500l/hr via 22mm pipe work, a small bore T piece is also incorporated in the output of this pump to provide a trickle supply for a Deltec PF500 calcium reactor which is controlled by an Aqua Medic pH computer, this keeps the KH at about 10 to 12, which I know is a little on the high side but the corals seem to like it.  A further Eheim 1250 returns water to the top of the weir via a Vectron 25 watt UV steriliser unit and Teco RA2400 cooler unit. Originally I had returned the cooled water directly to the main tank however anyone with half a brain should have realised that corals close to the output would not be very appreciative of being blasted with a cool water flow so I moved the output to the sump input where the water can be thoroughly mixed before being returned to the main tank.  

On the right hand side below the main tank is the 20 gallon holding tank which has an automatic level control remotely operating an R.O unit which is connected to the mains water supply fills the holding tank automatically to a predetermined level.  This tank has a heater, air stone and an old eheim powerhead all of which can be switched on individually to facilitate dissolving of salt for water changes, it is also the only tank with a cover.  A further old powerhead pump in this tank is used to move the water from the holding tank in to the third chamber of the sump. Water changes were a necessary chore and used to take hours, now at the flick of a few switches I can change 10% of the water with no effort whatsoever.

The remaining space between the sump and holding tanks houses two Aquamaster level control systems, a wave generator, Red Pharms ph computer, a UPS, CO2 bottle, the calcium reactor and most of the power distribution. A UPS is used because experience has shown that reliability of the mains electricity supply leaves something to be desired in this area therefore the main return pump, the air pump and the sump light are supported by the UPS.   

With a total of around 15 square feet of heated water surface area the system looses a considerable amount of water through evaporation, over four gallons per week.  With automatic top up the lose itself was not a problem however there was concern about the effect of high humidity and possible damp in the house and measurements confirmed that the humidity was in fact a bit on the high side.  A small dehumidifier from the local DIY seems to have reduced that to acceptable levels and as you would expect collects about four gallons of water each week.

One of the main aims of the project was to make the system as healthy and maintenance free as possible and whilst there are still a few minor tweaks to implement it’s getting pretty close.  As for the health of the tank, I don’t think we are doing too badly, corals are rampant and we constantly need to thin them out, as for the fish, we haven’t lost one from disease for years, (that’s not counting the two that jumped down the weir of course!) I put this down to the fact that we quarantine everything for 10 days before introducing it to the main tank and if it’s a fish treat it with Cuprazin to be sure.  

The current maintenance regime consists of pouring salt into the holding tank every 10 days or so, cleaning the protein skimmer and daily observation of the various dials and displays.  Once every four months I replace the activated carbon. Calcium and Ph are constantly monitored and salinity is measured at least twice a week.
Ammonia, Nitrite and Nitrate are checked every couple of weeks but I believe that if you know your tank well enough then you only need the test kits to confirm that your stock is healthy or in distress and why.

Supplements I use include Marine snow, live homebrew phytoplankton, Iodine, Molybdenum and Strontium.  I also add Vitamin & Amino Acid supplement to the foods.

I tend to keep the Calcium levels and Specific Gravity a little on the high side with KH of 10 to 12 and SG of 10.025 to 10.026, whilst this raises the running costs slightly the corals certainly seem to appreciate it and the fish seem happy enough. All other parameters seem fairly constant with ph 8.2 to 8.3, ammonia never being above 0, nitrite up to 0.02 maximum and nitrate, probably the greatest concern, has been up to 30ppm.  

Unwanted incoming stowaways;
Bristle worm 18 inches long.  Fast and vicious.
Bristle worm 24 inches long.  Faster and more vicious.
Mantis shrimp. Like lightning.
The capture of these three creatures could almost be the subject of an article in itself, suffice to say many very long nights often up to 3am with baited dark coloured glass bottle and a torch.
And a Nudibranchia.  Was halfway through his second coral before I noticed him.

Other incoming stowaways;
Sponges.  3-4mm dia. Just sit there and don’t grow.
Crabs.  Shy and retiring, hope they don’t grow too big.
Small bristle worms. Dwarf Lionfish loves them.
Molluscs.  Hundreds of them come out at night and clean the glass.
Clams.  Mostly died or been eaten, probably both.
Anemones.  Dozens of them, particularly in the sump. A few Aiptasia but not invasive.
3 x big snails. 400mm dia.

Current Fish;
Yellow Tang
Emperor Tang
Yellow Eye Tang.
Lipstick Tang
Dwarf Lionfish.
Volitans Lionfish.
Flame Angel
Coral Beauty
Rustic Angel
Maroon Clown
3 X Anthias Wreckfish

Sea Cucumber
Red Tube worm Protula bispralis
Small Bubble Anemone
3 x  Small Blue hermits
10 x Small Red hermits
Feather Starfish
2 x Flame scallops
Fire shrimp.  Thinking this fellow was short lived and having had this one for nearly three years, twelve months ago we bought a 20mm long Volitans lion fish.  The Lion fish is now 140mm long, the fire shrimp is still fine but hides a lot!!
In addition to the inverts listed above we have over 25 different species of various corals in 50 different colonies and apart from two or three recent purchases they have all been resident and growing for well over twelve months.  These include various types of Goniopora, Pulse Coral, Xenia, Scleronephthya, Capnella, Branch Coral, Leather Coral, Sarcophyton, Alcyonium, Star Polyp, Montipora, Pipe Coral, Clove Polyp, Turret Coral, Cynaria, Favia, Candy Coral, Echinopora, Flower Coral, Plerogyra plus several species that I can’t identify and a few that I have probably missed.

Finally my personal comments and the way I do things, my tips are purely my personal opinion and gained mostly through bitter experience and taking advice from those I respect.  I am sure that there are better ways of doing things but this seems to work for me.