King British Goldfish flake food is a good all-rounder. It's intended for cold-water fish and instructions say to ideally feed your fish three times a day as much as they can eat in two minutes. Well, if we did that, our fishies would be fat indeed! We have two goldfish that are just over a year old each and they're perfectly healthy on one feeding a day (that said, they do get bloodworm treats twice a week). Even if fed as instructions suggest, this food lasts forever. We're using a 55g tub at the moment and fully expect it to last until towards the end of 2010. It's not expensive, it is good quality, and you can't really ask for more than that, can you?

If you sometimes put too much food into the tank (if they don't eat it all within two minutes), don't worry too much. Occasional overuse won't pose a problem but if you do it consistently, be prepared for your tank's water quality to be lower much quicker.

(Please be aware that this kind of food is not suitable for when you are on holiday - you can't dump a load in the fish tank and expect it to last. Use something more appropriate and designed for that task, something like 7-day pyramid feeders! Or get a family member in with a spare set of keys.)