Feeding Amount Calculator
Enter your fish's total weight and the water temperature to get a daily feeding amount and a per-feeding portion, scaled to the season.
Feeding amount
60–74°F: a normal daily ration.
How the feeding bands work
The calculator uses four widely used temperature bands for pond fish: no feeding below 50°F, a light 0.5%-of-bodyweight ration from 50-59°F, a normal 1% ration from 60-74°F, and a heavier 2% ration at 75°F and above. The daily total is then divided across the number of feedings you plan to give that day.
Feed only what your fish clear in a few minutes at each feeding — uneaten food sinks, decomposes, and adds directly to the ammonia load your filter has to process.
Frequently Asked Questions
Why does water temperature change how much I should feed?
Goldfish and koi are cold-blooded, so their metabolism — and their ability to digest food — tracks the water temperature directly, not the air temperature or the calendar. As the water cools, their digestion slows down long before they stop looking interested in food.
Why stop feeding below 50°F instead of just feeding less?
Below roughly 50°F (10°C), a goldfish or koi's digestive system essentially shuts down. Food that isn't properly digested can sit and rot in the gut, which is worse than not feeding at all — this is why the dormant band recommends skipping feeding entirely rather than a smaller ration.
How is the daily amount calculated?
It's a percentage of the fish's total body weight per day: roughly 0.5% in the 50-59°F band, 1% in the 60-74°F normal band, and 2% in the 75°F-and-above active band. That daily total is then split evenly across however many feedings you give.
What if I don't know my fish's exact weight?
A rough estimate is fine for planning — the point of the calculator is to get the right order of magnitude and, more importantly, to get the temperature band right. Watch how much food is actually cleared within a few minutes and adjust from there.
General planning guidance only, not veterinary advice. If a fish stops eating outside the cold dormant season, or looks unwell, consult a qualified aquatic veterinarian rather than adjusting feeding alone.