Fish do not require as much food as is commonly thought and it is tempting to feed your fish whenever you want to see some activity or view an normally shy species. As a result fish are usually given too much food.

This has several drawbacks. Firstly, everything that is uneaten will break down quickly at tropical temperatures and begin to rot creating poor water quality and provide a breeding ground for disease. Alternatively, uneaten food will be drawn into the filter and cause premature clogging of the filter media, reducing its performance and increasing the filters maintenance schedule. Fish that eat a lot also produce a lot of waste and excess waste has the same detrimental effects.

Although some fish are termed "scavengers", and will consume crumbs left by other fish, it is a myth to assume that these fish will tidy the aquarium. No fish will eat bad or rotting food.

The frequency and quantity of food that a fish requires depends on the species. Some predators for example will eat a large amount in one sitting and may spend from several hours to several days digesting. Omnivores and scavengers search for small morsels throughout the day whilst others fish are nocturnal require feeding at night.

For the general community aquarium, feeding twice a day, morning and evening is a good staring point. I always fast the fish one day per week for two reasons. Firstly, this helps to (slightly) compensate for any over feeding during the week. Secondly, I never feed the fish after cleaning the aquarium to ease pressure on the reduced colony of filter bacteria. Feeding morning and night suits my community tank needs however, some of my aquariums contain nocturnal feeders and thus feeding ½ to one hour after lights out satisfies their natural routine.

Try to spread food evenly over the aquarium this gives the opportunity for all fish to feed. Feeding in a localised spot may mean that weaker or more sedate fish loose out to greedier competitors therefore use of a feeding ring should be avoided.

How much to feed, is generally a matter of trial and error. Begin feeding as much as the fish will consume in a period of around five minutes. A good guide for catfish is to feed ½ of one sinking tablet for every two inches of fish. Catfish can be gluttons so do not follow the five minute rule in this case. Tell tale signs of over feeding are waste food on the substrate, cloudy water and filters becoming quickly clogged.

It is worth noting that over feeding fish will do more harm than under feeding fish. Bear in mind that in the wild, fish have to hunt out food and in certain seasons food is extremely scarce. Fish do not get two square meals a day.

Obviously fry and small fish need regular frequent meals and should not go for more than one day without feeding however, healthy adults and sub-adults can survive happily if you you are away for for a up to a week and you will possibly return to an algae free aquarium if you keep catfish! If you are away for longer periods of time an automatic feeder can help but holiday blocks that dissolve over a period of time are cheaper and work well. If you decide to use an automatic feeder, run a test before going on holiday to ensure that it is feeding the correct amount at the correct times.

Asking a neighbour or friend to feed the fish is another option if you are away for longer periods but spend some time with them to explain your feeding routine and write down some instructions. Guaranteed, as soon as you have spoken to your friend they will have forgotten half of what you have told them! One way to ensure that a neighbour feeds the correct amount is to wrap a portions of dried food in tinfoil - one serving per package. Your friend cannot then go wrong. (Refer to The Aquarium While You Are Away for more information about what to do when leaving your aquarium for some time.)