Once you’ve carefully set up your aquarium it’s also important to look after the tank and your fish and to make sure everything continues to run smoothly. Changing the water for example is important as a way to make sure it stays fresh and doesn’t stagnate – however you must not completely change the water when you do this as this will be bad for the fish upsetting the careful balance you should have cultivated in the tank. Instead do a ‘partial’ water change every three weeks and make sure that you let your replacement water stand in a bucket for at least 24 hours to get rid of chlorine (which is poisonous to fish). Then switch off power to the thank (including pump and light, remove dirty water from the tank (about a bucket full), clean around the inside of the tank, then pour the new water in. Don’t use detergents of any kind. More regularly you should feed your fish. Make sure you use the correct food and feed your fish only one small pinch every two days (over eating is a very common cause of death for fish and left over food can pollute the water). If one of your fish appears unwell, then put it in isolation to prevent the spread of disease and be extra sure to immediately remove dead fish. Do not give your fish more than 8 hours of light a day and be careful not to overpopulate them. Do not leave your tank in direct sunlight.