Setting Up A Tropical Tank

Setting Up A Tropical Tank

If you are new to fish keeping please call into one of our branches and discuss your tropical fish requirements with our staff before you buy a tank. The first question to answer when planning your tank is what type of fish you want to keep.

What Fish & Which Tank?

There are hundreds of species of tropical fish readily available to you through the aquatics trade, many of which require special care and attention. Most people start with “community” fish, referring to species that will generally get on with each-other and that do not require any unusual care. Make sure that the fish you want to keep will be compatible with each-other, and be happy in whatever tank you provide for them.

When selecting fish for your community aquarium, it is important to note how big they grow, as this will determine the minimum tank size. It is also important to decide how many fish you wish to house. A rough guide is there should be 1cm of fish for every 25cm2 (1in per 10in2) of water. This would mean that in a 60cm x 30cm (24in x 12in) tank you could house up to 72cm (29in) of fish (e.g. equivalent to about 30 neon tetras). When selecting fish for your tank, always find out what sort of conditions they prefer, and if they have any particular requirements. It is always best to go for as big a tank as you can afford, not only because you can then house a better selection of fish, but also because it tends to be easier to maintain good water quality in larger tanks. Fish also benefit from a larger tank as they have the opportunity to behave more naturally. Tropical fish tanks usually start in size at about 60cm (24in), although there are many different shapes and sizes available. Nothing quite beats the clarity and visual beauty of a well-kept aquarium. But that clarity is the result of a number of essential pieces of equipment, without which your fish will not thrive, and your aquarium will always be lacklustre and murky. Remember, your aquarium must provide a complete environment for your fish, one that needs to be effectively maintained at all times.

Test Kits Tropical Food Internal Filters
External Filters Tropical Heaters Tropical Treatments
Tropical Air Pumps Tropical Lighting Tropical Accessories


One of the joys of the aquarium is the striking effect it has on a room- subtle, graceful and fascinating- you’ll want to give it pride of place. However, there are a number of simple rules for locating your aquarium to get the most from it and ensure the health and welfare of your fish.

Before you go out and buy your fish tank, it is important to find a suitable position for it. Once the tank is full of water it will be very heavy, and moving it will be time-consuming and stressful for the fish.

You’ve decided on the type of fish you want to keep, purchased all the equipment you will need to make them comfortable, now you need to decide where they will live.

You can work out roughly how much your tank will weigh with the following equation:

Length x Width x Depth (cm) divided by 1000 = weight in kg.

For example, using this equation a 60cm x 30cm (24in x 12in) tank will weigh around 55kg (excluding rocks and gravel).

The tank should ideally be sited in an area of the house that is:

  • Quiet
  • Away from areas of high activity
  • Away from any sources of heat or cold
  • Away from any potentially toxic substances (e.g. paint fumes, aerosols etc)
  • Easily accessible for carrying out any water changes that may need to be done
  • Positioned away from direct sunlight to help avoid algae problems

The tank should be positioned on a layer of polystyrene or cork, in order to protect its base.


Once you have decided upon a tank and found a suitable position for it, it is important to buy the correct equipment. Failure to buy the correct equipment will result in poor water quality and consequent fish health

problems. There are three key items of equipment to buy: the filter, heater, and light system. It is also possible to purchase a tank that already contains these items.


The filter is perhaps the most essential item of equipment. It serves to remove toxic ammonia and solid waste from the aquarium water, creating a healthy environment for your fish. Tetratec internal aquarium filters are specifically designed to work biologically and mechanically to maintain suitable water quality in your tank. Without a filter, the ammonia that the fish excrete would build up to toxic levels very quickly and ultimately kill them.

The internal filter is perhaps the simplest to install and use, combining biological, chemical and mechanical filtration in a compact unit designed to fit inside the aquarium, just below the waterline. The water is sucked into the unit through vents at the base of the unit by an impeller, a foam filter removes waste and allows bacteria to break down impurities, the clean water is then returned near the surface to allow aeration as the flow breaks the surface. Small and discreet, as long as the two filter cartridges are alternatively cleaned 'say every fortnight' this system can filter the water in a smaller aquarium several times an hour.

The FLUVAL Plus 2,3 & 4 combine mechanical, biological and chemical filtration within a fully submersible unit, which is quiet and effectively removes both solids and liquid waste products.

Plus 1 is a simple mechanical and biological filter, ideal for small aquariums and bowls (up to 45 litres) or as an additional filter in larger aquariums.


The heater is vital to the well being of your fish, as it controls the temperature of the tank. Tropical fish generally need a temperature of between 24 – 27ºC. All Cascade heaters are designed to accurately maintain the tank temperature at the desired level, incorporating an easy to use dial with which the temperature can be set.


Lighting serves two main purposes - providing essential stimulation to your plants and fish, while giving a beautiful visual effect. The right lighting can both enhance the look of your aquarium, as well as recreating the changing patterns of sunlight in nature. Fluorescent lighting is best - it is efficient, covers the length of the tank and can be selected to provide the optimum light for your aquarium.

Having a light in the tank serves two purposes. Firstly to allow you to see the fish, and secondly to promote plant growth.There are many types of light available but most people start with as tandard fluorescent tube (bought from an aquatics outlet and designed specifically for use on fish tanks). Different plants require varying levels of light, with some species requiring more light than others. Light bulbs will normally indicate the light intensity that they produce, and if you intend to keep a lot of plants then it is usually best to get a bulb specifically designed to encourage their growth.


It is important to provide your fish with a home that they feel happy in, as this will result in them behaving more naturally and giving you more pleasure. There should be plenty of hiding places where the fish can retreat to if they feel threatened, as well as either plastic or real plants for them to swim amongst. Failure to provide sufficient hiding places will result in the fish being permanently stressed and unhappy, with the inevitable consequence of them suffering from health problems. Hiding places can be constructed from bogwood, rocks, plants and so on. Always buy rocks, wood and substrate from an aquatics outlet, as you can be sure that these are safe for use in your tank.

The bottom of the tank should be covered in a layer of well-washed gravel or aquarium sand. Certain fish prefer certain substrates, for instance some loaches and catfish like to bury themselves in sand. The depth of the substrate will depend on whether you are planning to keep live plants or not. In a tank without plants it is better to have a thinner layer of around 1 – 2cm (0.5 – 1 in) as this will trap less waste, and therefore be easier to keep clean. In this sort of tank it is possible to create the effect of a planted tank by using plastic plants. Whilst still looking realistic, plastic or silk plants do not require the care that real plants need. They are also ideally suited to tanks containing plant-eating fish. If you are planning to keep live plants, then the substrate should be slightly deeper, ideally around 5 – 7cm (2 – 3 in). Live plants will need correct lighting levels, as well as weekly additions of Tetra FloraPride plant fertiliser in order to encourage strong growth.


Once the tank is in position, equipped and decorated, it is time to fill it up. For general community tanks, tap water is usually suitable, and under no circumstances should you use mineral water, rainwater, or water from a household softener. Although tap water usually contains the correct minerals for our fish, it also contains harmful chlorine and heavy metals.

These must be neutralised before the water is safe for fish.This can be done by adding Tetra Aquasafe to the tank once it is filled up. Failure to do this will result in severe damage to the fishes’ gills. Tetra AquaSafe should also be added to the tap water every time a water change is done. When you fill the tank, you should pour the water onto a dish, or similar object, in order to prevent it disturbing the layout of the tank. Once it is filled, the heater and filter can be switched on and the water left to warm up. A thermometer should be added to the tank so as you can monitor the temperature.


Once the temperature is stable, A bacterial booster should be added to the tank, in order to promote the development of beneficial filter bacteria. A day or two after this, the first few fish may be added. It is important to stock the tank slowly, adding just a few fish at a time. This will allow the filter bacteria to cope with the amount of ammonia that the fish are producing.

During the initial stages of stocking the tank, 25% water changes should be performed weekly, replacing the old water with tap water conditioned using Tetra AquaSafe. Doing this during the initial stages will help the filter to maintain suitable conditions within the tank. Once the tank is fully stocked and the filter is “mature”, you will only need to perform water changes once every 3 to 4 weeks.

To start with, the fish should be fed once a day, only feeding the amount that they will consume within a few minutes. Any uneaten food should be removed from the tank to prevent it rotting down. Once the tank has been running for a while, you should increase feeding levels to two to three times a day, still only feeding what the fish consume within a few minutes. Make sure that you use one of Tetra’s range of quality fish foods, as they are designed to meet the fish’s dietary needs whilst only producing a minimum of waste. TetraMin Pro and TetraMin are specially formulated to meet the requirements of all tropical fish, whilst there are a range of other Tetra foods to compliment them.

Creating the right environment to start with will help to ensure that your fish remain healthy and happy.

Thanks to Tetra and Rolf C Hagen for some of the information on these pages