• Place the empty aquarium and stand on a flat solid surface in a well lit position but not in direct sunlight. Place a flat piece of Styrofoam on the stand beneath the tank, this will prevent it smashing if the tank is jarred. Direct sunlight will heat the tank water during the day and cool it at night and as a result your fish will suffer stress diseases. Direct sunlight will also cause too much algae to grow and the tank will be difficult to keep clean.
  • Consider adding a background to your tank, and soft lighting to allow easier fish watching.
  • One litre of water weighs one kilogram and there is the additional weight of the tank, stand and other equipment. The floor surface you have chosen must be able to support this total weight. Placing your 200 litre tank on the rickety shelves Uncle Tom made, is not the best idea.
  • Half fill the aquarium with water (clean tap water is suitable). If a bottom filter is to be used, install it at this stage. Then place sand on the bottom with pebbles and stones for decoration. Make sure you also provide hiding places for your fish. Fish like to hide, if they can’t find a spot to hide, they will swim and swim looking for one. Not good, Nemo will not be happy. Pebbles only instead of sand can be used, but excess food will often fall between the pebbles and spoil, meaning constant water changes. DON?T get sand from the beach, metals will usually leach from it killing your fish. Anchor in some water plants which will help oxygenate the water. Try getting a mix of plants the fish will eat, for roughage, and ones they won’t eat, so your tank does not end up bare.
  • Complete the filling of the tank to within five centimetres of the top. If you have purchased active fish, or they are likely to be disturbed, they may jump out of the tank, so cover the aquarium with a glass top that is raised sufficiently to let air in.
  • A water filter operated by a small electric submersible motor will help to keep the tank clean, but if your fish are being fed too much food, thus excreting too much, algae will still overgrow in the tank.
  • The same motor can operate an aerator that pumps tiny bubbles of air into the water. These aid in circulating the water (which helps with oxygenation, since most oxygen exchange takes place at the surface). Bubbles also show that the filter is working properly. Many filters use a combination of charcoal filters and fine sponge filters to remove solids. These will need to be regularly cleaned and replaced. You can stock the tank with 40% more fish if an aerator is used. Many fish shops now sell combination aerator/filters removing the need for a water pump.
  • For tropical fish a heater and thermometer are also needed to keep the water at the right temperature (22? C – 24? C for tropical and marine fish and 15? C – 20? C for coldwater fish). The effects of central heating and other forms of room heaters should be considered. Water temperature in tanks should be checked daily and maintained within a range of 5? C of the optimum temperatures.

Let the newly filled aquarium stand for about 3-4 days before buying your fish. Fish are sold in a plastic bag and this should be floated on the surface of the tank water for 30 minutes to allow the water and fish in the bag to reach the same temperature as the water in the tank. This way, fish will not get be shocked by being moved to water at a different temperature. A sudden temperature shock of even a few degrees can kill the fish. After this time, add tank water very slowly to the bag to allow the fish to acclimatize to the tank water (and thus prevent osmotic shock). Then decant the fish into the tank.

New aquariums take about 2 – 3 weeks to ‘settle down’ after the fish have been added. During this time tanks should be tested daily for nitrates and ammonia (using kits which can be purchased cheaply). Nitrates and ammonia are very toxic to fish, however they are converted to more harmless nitrates by the action of “nitrifying bacteria”. Once the bacteria reach a balance in the tank, they will convert the nitrates and ammonia as it is produced. The plants use the nitrates in the water.

Change about a quarter of the water every week whether it is dirty or not. Poisons can acculumate even in seemingly clear tank water. Be very careful to ensure that the replacement water is at the same temperature as the tank (to within two degrees) If the tank is particularly dirty replace about 1/3 of the water at once, clean the filter and then remove and replace a quarter of the water each day until it is clear again. Carefully monitor the nitrate and ammonia levels.

Veterinary Surgeon, London at Blue Cross UK | + posts

A London based Veterinary surgeon, Sanja is also an avid writer and pet advocate.