Building our own fishroom 2 (Dr. Oliver's project)

by Andreas Iliopoulos

Some months ago, Dr. Michael K. Oliver gave us the idea to write an article concerning the building of a fishroom. The truth is we liked the idea a lot and when he posted us the overview of his basement, which should be turned into a fishroom, we did a little work and this is the result.

What we made is based on the dimensions of Dr. Oliver’s basement, but you may modify those proposals  according to your space and your specific fishkeeping needs. The fishroom we designed here is kind of laboratory fishroom suitable for keeping and breeding mid-size to relatively large cichlids and not a fishroom for display tanks, but the concept remains the same.

What we have here is a basement with an available space, at the the corner - approximately 5,7 m² on the one side and 1,62 m² on the other. The height of the basement from the floor up to the ceiling is 1,98 m (see diagram below)

The one side of this fishycorner is 3,8 m long and 1,5 m deep and can house a two floor rack with seven (7) tanks on each floor, using 1 m of its 1,5 meters of depth. On the other side, that is 4,3 m long and 0,61 m deep, we may use of the 2,70 m of its length to install another two floors rack with six (6) tanks on each floor. Eventually twenty six (26) tanks of an adequate size (as we shall see below) can be housed in this relatively small space. The total water capacity reaches the six thousand liters (about 1.500 g). We believe that this is a decent fishroom for keeping and breeding cichlids with enough water volume to work with.

A. Racks

The construction of racks on which we want to put water tanks must be the result of careful evaluations and calcilations to minimize any danger of collapsing and be as functional as possible. The available materials for such a construction are wood, iron and aluminum.

Wooden racks are easy to dismantle and a pleasure to look at, but on the other hand, wood must be cured and covered with several layers of water protecting materials to last for long time in a wet environment. They can be considered as relatively cheap, especially if you construct them yourself. A draw back is that wooden beams must be thick enough to hold all this weight, in opposition to iron or aluminum beams that can be slimmer for the same weight. This is translated in some loss of our available space. Wooden racks are easy to build, if we have some basic tools, like an electric auger, long screw eyes, screw drivers, a level, carpenters’ glue and lot of patience. All we need is to take perfect measures, go to a lumberyard and order to cut for us the desirable dimensions of the beams we’ll have to use. Prefer to order already cured wood. Then with the valuable help of one or more good friends we can mount the wooden pieces together. Then we’ll have to cover our construction with a good quality primer and after that with, at least, a couple of layers of water-resistant varnish. You may use pinewood (the cheaper solution) or better quality and more expensive of course - woods as beech wood, chestnut wood, oak wood or tropical woods that they are water resistant by nature and far more expensive.

Iron is cheap but the construction of iron racks must be done by a professional, as the tools (like the electric winding unit) are not the common tools, that usually are available in our houses’ tools collection. Besides it is not so easy to achieve the right windings if you are not a professional and if you attempt to construct an iron rack without being qualified to do so, it can be absolutely dangerous. The drawback of iron is rust, so the construction must be covered with a good quality primer and after that with several hands of waterproof paint. It is good to protect the legsof iron racks with plastic pads, to prevent them from rust at the most critical part of the construction. It is also essential to conserve the construction from time to time. This means you’ll have to apply a good quality water-resistant paint on the construction when it asks for it (once a year would be perfect). There are paints that they may used directly on the rust, without any stain before. Another option is to use electroplated iron, than plain iron for the construction of the rack.

Aluminum is the perfect material for this job. It is light and it is practically immortal”. Additionally if you use electrostatic coated beams, then you forget about it once and for all. And you may choose any color you find that matches to your basement. The construction of aluminum racks must be made from a professional too. It is also very expensive compared with wood, iron or electroplated iron. The workers’ wages are also expensive, although the tools are need for such a construction are cheap and easy to use. All you need is a clinch tool and rivets. There is a special technique to fit the beams together. The best craftsmen use aluminum profiles in the joints that they can fit within the beams, so rivets do not rumple them when clinched and practically the beams’ thickness and durability is doubled. Additionally the joints are not evident.

Construction of the racks

I chose iron for this virtual fishroom in order to keep the cost as low as possible. The iron beams are 4 cm x 4 cm wide ones. The thickness of metal itself is 4mm. The racks consist from legs114 cm long and frames.

For the lower floor I designed one frame with 3,8 m of length and 1 m of depth and for the upper floor one more frame with the same dimensions. Sixteen legswith a length of 23 cm will support the frame of the lower floor and sixteen more with a length of 83 cm will support the frame of the second floor.

For the second rack I designed one frame with a length of 2,7 m and a depth of 0,61 m, for the lower floor and one frame of 2,7 m and a depth of also 61 cm for the upper one. Fourteen legswith a length of 23 cm will support the lower frame and sixteen more with a length of 83 cm will support the upper floor’s frame.

The one of the frames is welded on the legsto form the lower floor while the second one is welded on the top of the construction to form the second floor. I let a 23 cm space from the basement floor up to the first floor, so there is a place to install a drainage system underneath the rack. I also let an 83 cm space between the lower and the upper floor. 60 cm tall aquaria can be placed on the lower floor, letting a space of 23 cm between the upper side of the tanks and the second floor, so lights can be placed and tanks’ maintenance will be easy. On the top floor can be placed also 60 cm tall tanks. This way we have a space of 24 cm from the top of the top tanks to the ceiling, so lights can be placed and the necessary operations for the tanks will not be difficult to be done.

The same way we shall work for the construction of the second rack.

B. Tanks

The iron racks now, define the dimensions of the tanks for us.

On the first rack we can install seven (7) tanks on the lower floor which will measure (L x W x H) 49 cm x 100 cm x 60 cm and a water capacity of about 290 liters (75 g) each. On the upper floor we shall install five (5) tanks which will measure (L x W x H) 53 cm x 100 cm x 60 cm and a water capacity of about 315 liters (82 g) each, one (1) tank with dimensions (L x W x H) 55 cm x 100 cm x 60 cm and another one of 54 cm x 100 cm x 60 cm. These last two tanks measure a water volume, more or less, of about 320 liters (83 g) each. So we have an overall of fourteen (14) tanks with a total water volume of more than 4.000 liters (about 1.000 g).

The second rack can hold six (6) tanks of (L x W x H) 40 cm x 61 cm x 60 cm, on the lower floor, with a water volume of about 145 liters (38 g) each and four (4) tanks of (L x W x H) 43 cm x 61 cm x 60 cm, with a capacity of 157 liters (about 40 g), one (L x W x H) 47 cm x 61 cm x 60 cm and another one with (L x W x H) 46 cm x 61 cm x 60 cm and their capacity is about 170 liters (about 44 g) each. This makes us an overall of twelve tanks with a total water volume of about 1.800 liters (468 g).

Number of tanks (1st rack)

Dimensions L x W x H (cm)

Volume (liters)


49 x 100 x 60



53 x 100 x 60



54 x 100 x 60



55 x 100 x 60


Number of tanks (2nd rack)    
6 40 x 61 x 60 878,4
4 43 x 61 x 60 629,52
1 46 x 61 x 60 168,36
1 47 x 61 x 60 172,02
26   6.146,3


I preferred motor driven internal filters to supply each tank. For the fourteen (14) tanks, I designed an internal filter with 17 cm of width. The first compartment which is the inlet chamber, has a hole drilled on the lower part of it. The diameter of this hole is 3,5 cm. This compartment can have mechanical and/or chemical media or even a thermostat in it. The length of this chamber is 7 cm. The last compartment, which is the water outlet compartment has also a hole drilled, but on the upper part of it. This hole has a diameter of 16 mm, and through it the filtered water turns back into the tank. Its length is 12 cm. The rest chamber, in the middle, is the biological substratum chamber.

The way I designed these filters is the same way I designed the filter for dr. Reklos’ non – m’buna tank and for the filters I use for my stock tanks, or the way it is shown on the above 3D diagram, in which the water way is vertical.

Of course I believe that the horizontal water way is far better (especially when water pumps are used, as in such a case, we may “work” the tanks with as less water level as we desire, as far as the water pumps are covered with water. This option is essential when we are about to perform a treatment in the tank as we can use less quantity of the medication, we may also perform a short time bath or a dip, with no further problem. You can take a look here for more details on this particular filter design http://www.malawicichlidhomepage.com/haps/filter_diagram.html For the other twelve ones the concept is the same and the dimensions of the compartments are alike.

The reason for the motor driven filters is associated with the filters’ design. This design allows us to work with as much water as we need, as long as its level covers the water pump on the third chamber. We prefer water pumps with an outflow control, to reduce or increase the water turnover. So we may use the tank with several ways. We can perform baths or dips in tanks like these, or we can treat less water volume, as drugs and medications are expensive sometimes. We also simply can use less water volume if the bioload of the housed animals do not justify the whole tank’s capacity. This way we shall have less water to heat, treat or partially change and we can save ourselves some money. The water pumps that may give us these turnovers do not consume less than 9 and more than 19 Watts each.

Another utility that can be added on each of the tanks is a hole drilled inside the one of the three filter compartments (preferably the compartment that the water pump is housed in). This hole can have a diameter of 2,7 cm 2,8 cm, to fit a drainage fitting of a ½’’ of diameter. With a small ball or gate bulb, connected after the fitting we may empty our tanks easily and fast avoiding any dripping. If you visit the page http://www.malawicichlidhomepage.com/haps/whole_tank_hydraulic.html, of MCH, you may have an idea for this utility. In this page it is clearly seen the drainage fitting on the diagram that our 3D designer, Takis Tsamis, has prepared for this purpose.

Construction of the tanks

We may use glass or acrylic plates to construct water tanks. I prefer glass water tanks for a fishroom though.

Acrylic is expensive and scratch easily. Although it is more transparent than glass, it yellows as time passes and tinctures from dyes that may are contained in some medications, it is very friendly to algae but it is very light. The construction of acrylic tanks claims a special technique with some sort of solvents and it is better to let this job for a professional. Acrylic can be drilled easily, so we may make holes on it any time we want.

● Glass on the other hand is heavier than acrylic, as thicker glass plates than the acrylic ones must be used to construct the same tank. The holes must drilled before we glue the glass plates together. Glass tanks can be made from us. All we need is plenty of 100% good quality silicone (I usually use Den Braven, Bayern, Simson, or General Electrics), a silicon pistol, a lot of toilet paper, scotch tape, a razor, a measure, alcohol or acetone (which it’s cheaper than alcohol), a marker and patience. We’ll have to be very careful with our measurements and we’ll have to pay a lot of attention, as glass cuts nastily.

First we’ll have to clean the glass plates thoroughly with either pure alcohol or acetone and toilet paper, then glue a Styrofoam plate under the bottom glass. It is better to use as dense Styrofoam as we can find.

Then we glue the first long plate on the bottom glass and next the first short one on the bottom glass plate and on the one vertical side of the one of the long plates. The second short plate must be glued on the other side and the bottom too and at last the long side, both on the bottom and on both vertical sides of the short glass plates.

When all the glass plates are glued together we use the scotch tape to press and secure the glass plates together and immobilized.

Some of the silicon will be spit out after this gentle pressure. We use our fingertip to apply the excess of silicon in the inner surfaces of the tank, as putty, at couplings where the glass plates contact each other. Use only one finger, so all the “stocked” parts will have equal silicone in amount.

We let the excess of silicon, that it is spitted out on the outer surfaces of the tank, to harden and then we remove it by a razor (preferably next day). The next day we glue the glass strips that will secure our construction and will hold the glass covers too. We do as mentioned above with the excess of silicon that will be spitted out from the couplings.

On these specific racks we may install, instead of the tanks that were designed as above, bigger tanks as long as we need one or two large display tanks on the position of three or four smaller ones (like the example I give below). In such a case we must use thicker than 4 mm iron boards (5 or 6 mm, ruggedized iron boards are fine).

Number of tanks (1st rack)

Dimensions L x W x H (cm)

Volume (liters)


265 x 100 x 60



49 x 100 x 60



55 x 100 x 60



54 x 100 x 60


Number of tanks (2nd rack)




40 x 61 x 60



222 x 61 x 60



43 x 61 x 60









For mechanical and chemical media we shall use the market available ones (aquarium moss, charcoal, peat etc). For biological substrate we may use, except the commercial plastic balls (bioballs or bactoballs) and ceramic cylinders manufactured for aquarium use, the plastic rolls that hairdressers use to form permanent waves on women hair, or holystone pieces or other comparative – but safe - porous materials.


For this particular fishroom it is not need to use very special lights. We need plain day light fluorescent tubes, but I find as essential to use watertight nozzles and place all the shunt transformers, starters and plugs on the wall, away from the contact with the iron racks and the humid environment near the water tanks. It is advised the construction of a ply wood container, placed near available airstream on the upper region of a wall which will contains shunt transformers, starters, jacks, plugs and other equipment that it is wise to be kept away from moisture.

It is also good to connect all our lights with timers (timers can be put in the ply wood container too), so lights will turn on and off on a steady basis and the desired photoperiod is going to be fixed this way.


Near the sink we may place a couple of plastic cones, up side down, to use them for Artemia salina (brine shrimp) cultivation.


I also suggest to isolate the walls and the ceiling of the fishroom with 20 mm thick Styrofoam plates of a high density (blue or gray ones with the commercial name ROOFMATE are the best). It is a one-time cost but it will save energy and money for as long as we operate our fishroom.

It is also advised to use watertight sockets to plug thermostats and water pumps on. It is good to tell an electrician to install a security relay on your electric board if it has not one already installed.

We may also change a bit the way of the construction of the racks and removing some of the smaller tanks from both racks, we may install one or two really large display tanks for our pleasure and for keeping our adult breeders, instead.

Fishy comments

Use the aquarium water from the partial changes (if it is free of medications) to water your garden or your potted plants. It’s a natural fertilizer.
Use the cooler down floor tanks for species they like slightly cooler water than the other species you keep.
Use the unloaded upper floor tanks as water containers. Use their water for a partial water change for another tank.
Use the lower floor tanks for hospital tanks, spawning tanks and quarantine tanks. Prefer the rack with the smaller tanks (40 cm x 61 cm x 60 cm).
Use screens to separate tanks in compartments, to increase the diversity of species you keep.
Use an old refrigerator to store drugs and foods in it. It is dry, dark and isolated and you do not have to buy it, but just to find it and carry it home.
Build one fishroom for yourself soon. You’re going to love it.

All diagrams were prepared by Takis Tsamis to whom special thanks.

Back ] Up ] Next ]

Site Search 

Contact us


Malawi Cichlid Homepage © 1999-2006. All rights reserved.