So you have just set up your tank, you have everything in place, the pump is ready to aerate, the filter ready to filter and the heater ready to heat, you have filled the tank with clean water and have planted your aquarium beautifully and you are eager to rush out to the pet store and buy a load of fish.

No. Stop!

When the tank is initially set up it needs to adjust, the temperatures must be correct and the environment must establish itself. Friendly bacteria must build in the filtration system needed to break down the ammonia levels in the water once fish are introduced.

Once you have filled the tank and have the dcor, plants heater and filter in place then leave the water to rise to room temperature before turning on the heater. Gradually let the water heat to around 76f depending on the fish you will be buying (always check with your aquarist for the ideal temperature for the fish you want).

Once the tank temperature is at the right level turn on your filter and air pumps, the temperature will dip a little but will soon catch up, leave the tank to acclimatise and develop for a few days. Some aquarist leave a two day gap I tend to leave the tank for seven days to ensure the friendly bacteria has a chance of developing. Feed the water and your plants during this time as this will encourage the bacteria to develop in the filter sponges.

When you have selected the fish you want from your aquarium centre float them in the bag they came in on top of your water, this will allow the fish to settle and the temperature of the water bag to adjust to the water temperature in the tank, this is important as a sudden change in temperature can paralyse, shock even kill new fish. Float the fish for around twenty minutes then slowly mix some of the tank water in the bag so that you can view any changes in the fish. If you are satisfied with that the fish are ready slowly release the fish into the tank.

Sit for a while with your new fish, check that they are swimming correctly and that the fish are not gasping for air, twitching or showing any other signs of distress. Do not feed them, more than likely they will have been fed at the aquarium centre. Overfeeding kills more fish than starvation.

Over the first few days keep a good check on your fish, test the water and be vigilant of any changes. Feed them only around once a day so that rotting food doesnt build up.

Adding large amounts of fish makes ammonia levels soar in the tank and the filter will not be able to cope, introduce only a small amount of fish at a time, if the fish are small then introduce them a few at a time over a few weeks. If the fish you choose are fairly large then you should only introduce one at a time. Stocking the tank is a crucial time whether for the first time or restocking. More fish means more waste, adding all of the fish at once will mean that a sudden surge in toxins are introduced to the water, this can be fatal. It is much better to be patient and allow the fish and the delicate environmental balance of the aquarium adjust before adding any more.

This method may take longer than you had originally anticipated but if you are going to enjoy your aquarium then being patient will be one skill worth developing.