FAQ: Food for fish

Flakes float longer, granules sink slowly and tablets drop to the bottom. Choose by where your fish feed.

A common guide is as much as the fish eat in a few minutes. Uneaten food pollutes the water.

Flakes are thin, soften quickly and suit small and surface-feeding fish. Granules are denser, keep their shape longer, crumble less and pollute the water more slowly, so they are often chosen for medium and larger fish.

A granule should fit easily into the fish’s mouth: micro granules are chosen for small tetras and rasboras, and larger ones for bigger cichlids or goldfish. Manufacturers often state the granule size in millimetres and which fish it is for.

Tablets sink quickly and soften slowly, so they are handy for bottom-feeding fish – corydoras, catfish, loaches – and for shrimp. They are best added in the evening or with the light off, when nocturnal fish are more active.

Sticks are elongated, usually floating pieces of food for larger fish, especially pond fish and koi. They stay on the surface for a long time, so it is easy to see how much the fish eat.

Chips are thicker, denser pieces of food that break down more slowly and crumble less than flakes. They suit medium and larger fish and are often sinking.

Wafers are flat, fast-sinking discs of food, usually with plant ingredients or spirulina. They are meant for pleco catfish and other bottom-grazing fish that eat slowly.

Floating food suits surface feeders, bettas, gouramis and pond fish, because you can see how much is eaten. Sinking food suits fish that feed mid-water or near the bottom and reduces the risk of fancy goldfish swallowing air.

Gel food is made from a powder mixed with water or sold ready-made. It is moist, easy to digest and handy when you want to mix vegetables or frozen food into it.

Powder is very finely ground food for fry, very small fish and shrimp. It drifts in the water for a long time but pollutes it quickly, so dose a little at a time.

Yes, flakes can be crushed between your fingers into smaller pieces for small fish or fry. Still, micro granules or powder are more practical for very small fish, as their nutrients wash out more slowly.

A good-quality staple food can meet most fish’s needs, but variety helps. Adding frozen or live food a few times a week makes fish more active and colourful and helps them breed.

A staple food is a complete everyday diet with balanced protein, fat, carbohydrates, vitamins and minerals. Specialist foods complement it: colour-enhancing, plant-based or frozen treats.

Fish differ in diet: some are carnivores, others herbivores or omnivores, and they feed at different levels in the water. Specialist foods, for example for cichlids, goldfish or bettas, match the needs and mouth size of particular species.

Most adult aquarium fish need feeding only once or twice a day in small portions. Young fish and fry are fed more often, and some predatory fish less often.

Fry grow fast and have tiny stomachs, so they are usually fed 3–5 times a day in very small amounts. Remove uneaten leftovers promptly, as the water in a small container quickly deteriorates.

Signs are uneaten food on the bottom, cloudy water, a film on the surface, fast-multiplying snails and algae, and tests showing ammonia or high nitrate. The fish may have swollen bellies and long strings of faeces.

Yes, fish that get too little food for a long time become thin with sunken bellies and pale colours, and shoaling fish grow more aggressive and nip fins. If you notice these signs, slightly increase the portions or the number of feeds.

It is best to feed at least half an hour after the light comes on and no later than an hour before it goes off, when the fish are active. Nocturnal fish such as some catfish prefer to eat after dark.