Goldfish flakes
Goldfish flakes are a floating, complete staple food designed to cover a goldfish's everyday nutritional needs, and for most tanks they should make up the bulk of feeding alongside the occasional sinking pellet or treat for variety. The single most common mistake with them is not the flake itself but how much goes into the tank at once.
What flake food is actually for
A decent flake food is formulated to be a complete diet on its own, covering protein, vitamins and the general nutritional needs of a goldfish rather than being a treat or an extra. Look for one that lists real fish or fish meal fairly high in the ingredients rather than being mostly fillers.
Flakes float and soften quickly once wet, which suits goldfish who feed at the surface, but it also means uneaten flake breaks down into the water fast if it is not eaten within a few minutes — which is where most of the practical problems with feeding actually come from.
How much and how often, as a general rule
A common, sensible approach is to offer only as much as will be eaten within a couple of minutes, once or twice a day, and to remove anything left over rather than letting it sit and dissolve. Goldfish will beg for far more than they need, and that eagerness is not a reliable guide to how much they should actually be given.
If you are ever unsure how a particular food should be portioned for your tank size and number of fish, the packaging and a specialist retailer are better guides than working it out by trial and error, since it varies with tank size, filtration and stocking levels.
Why overfeeding is the most common mistake
Uneaten flake does not just go to waste, it breaks down and adds directly to ammonia and waste levels in the water, which is a far more common cause of a cloudy tank or unwell fish than anything in the food itself. Most goldfish problems traced back to feeding are actually overfeeding problems.
Cutting back to only what is eaten quickly, and being consistent about removing anything left, does far more for water quality and fish health than switching brands ever will.
Flakes, pellets and other foods
Flakes suit surface feeding, while sinking pellets suit fish that spend more time lower in the tank, and many owners rotate between the two, plus the occasional vegetable-based treat, for variety rather than relying on one food exclusively. Neither is inherently better — it depends on your fish's feeding habits and what your tank setup suits.
If you keep more than one goldfish and notice some feeding well at the surface while others hang back lower down, offering a mix of flakes and sinking food in the same feed makes sure everyone gets a fair share rather than the more confident fish at the top eating most of it.
What we stock
Everything below is in stock with us, priced with delivery worked out, and packed and posted by hand in the UK.
Tetra Goldfish Flakes
Complete goldfish flakes in several pack sizes, with a shared formula across the family
From£3.02
Tetra Goldfish Granules
Complete granules for goldfish, with a shared formula across both pack options
From£3.98
Tetra Prima Mini Granules
Slow-sinking granules for mid-water and bottom-feeding fish, blending herbivore and omnivore diets
£6.10
Tetra Aquasafe
A water conditioner that neutralises chlorine and heavy metals, with an added vitamin B mix
From£6.41
Tetra Pond Fish Food Variety Sticks
Complete Tetra Pond Variety Sticks in three colours, across four pack sizes
From£6.41
Tetra Koi Pond Fish Food Sticks
Complete fast-soaking Tetra Pond Koi Sticks, available in four pack sizes
From£6.41
Tetramin
Complete TetraMin flake food for ornamental fish, offered across several pack sizes
From£2.39
Tetra Temperate Flakes
Complete flakes for subtropical fish kept at 18–23°C, with vegetable ingredients
£6.99
Tetra Pond Fish Food Sticks
Complete fast-soaking Tetra Pond Sticks for pond fish, in seven pack sizes
From£4.77
Tetra Japan
Sinking dry pellets for fancy goldfish, with pack-specific label information shown clearly
From£4.56
Common questions
- How often should I feed goldfish flakes?
- Once or twice a day, offering only as much as will be eaten within a couple of minutes, is a common and sensible approach for most tanks. Removing anything left uneaten afterwards matters as much as the amount you offer in the first place.
- Why is my goldfish tank cloudy after feeding flakes?
- This is almost always down to overfeeding rather than the flake itself — uneaten food breaks down in the water and adds to ammonia and waste levels, which is the most common cause of cloudiness and poor water quality in a goldfish tank.
- Can goldfish eat only flakes, or do they need variety?
- A good quality flake can serve as a complete staple diet on its own, but many owners rotate in sinking pellets or the occasional vegetable-based treat for variety. Neither approach is wrong, provided the main food is a genuinely complete one.
- Do flakes sink or float, and does that matter?
- Flakes typically float and soften as they sit on the surface, which suits fish that feed near the top of the tank. If your goldfish spend more time lower down, a sinking pellet alongside or instead of flakes may suit their feeding habits better.
Written by Matt Garnett, who runs Giddy Pets and is a lifelong pet owner — not a vet. This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your animal. How we write these guides.