Types of fish food
- Flakes. The standard food for most community tropical and coldwater fish. They float first and then drift down slowly, so they suit fish that feed at the surface and in mid-water.
- Granules and micro pellets. Hold together better than flakes and sink at a set speed, which suits mid-water feeders and makes portioning easier. Pellets also work better in automatic feeders, where flakes can clog.
- Sinking wafers and tablets. For bottom feeders such as catfish, loaches and plecos, which may never see food that floats.
- Pond sticks and pellets. Larger floating foods for goldfish and koi in garden ponds, often in growth, colour and low-temperature or wheatgerm-based versions.
- Frozen and freeze-dried foods. Bloodworm, brine shrimp, daphnia and similar. Useful as variety or for fussy and carnivorous species.
- Holiday and weekend feeders. Slow-release blocks for short absences.
Matching food to your fish
Think about where the fish feed (top, middle or bottom), what they eat in nature (plant matter, insects, other fish) and how big their mouths are. A tank with tetras, corydoras and a pleco needs at least two foods: something for the mid-water fish and a sinking food for the bottom dwellers. Goldfish and tropical fish have different requirements, so use food labelled for the type of fish you keep. Colour-enhancing foods contain natural pigments such as astaxanthin and spirulina.
How much to feed
Give only what your fish eat in two to three minutes, once or twice a day, and net out leftovers. Fish do not need to be full; a slightly rounded belly is enough. Many healthy adult fish can go a few days without food, which is safer than a holiday feeder that pollutes a small tank. Pond fish eat more in summer and much less in cold water, so follow the temperature guidance on the pack.
Storage
Fish food loses vitamins once the tub is opened, particularly vitamin C, and can absorb moisture and go mouldy. Keep the lid closed, store it somewhere cool and dry, and buy a size you will use within a few months rather than a large tub that lasts a year. Do not feed food that smells musty or has clumped.
Common mistakes
- Feeding every time the fish come to the front of the tank.
- Using only flakes in a tank with bottom feeders.
- Buying large economy tubs for one small aquarium.
- Leaving holiday blocks in a small tank where they foul the water.
Common questions
How much fish food should I give?
A common rule is to give only what your fish finish in two to three minutes, once or twice a day. If food is reaching the bottom and staying there, you are feeding too much. Overfeeding is one of the main causes of cloudy water and ammonia problems.
Can goldfish eat tropical fish food?
Occasionally it will not harm them, but it is not ideal as a staple. Goldfish foods are formulated for coldwater fish with different nutritional needs. Use a goldfish food as the base and add variety such as peas or frozen daphnia.
How long does fish food last after opening?
Fish food gradually loses vitamins once opened and can go stale or mouldy if it gets damp. Many keepers aim to use a tub within a few months. Store it closed in a cool, dry place and buy smaller tubs for small tanks.
Can I leave my fish for a week without food?
Healthy adult fish can usually cope with a few days without food, and some can go longer. For a week away, a trusted person with pre-measured portions or an automatic pellet feeder is safer than a slow-release block, which can foul a small tank. Young fish need feeding more often.