Many new fish that refuse food at home are not ill; they simply do not recognise what lands in front of them. A fish raised on sinking granules may ignore flakes at the surface, and a fish used to frozen food may watch dry food drift past without reacting. Asking about the current diet before you buy turns the first fortnight from guesswork into a planned changeover.
The Food Itself: Type, Form, and Size
Ask what the fish is eating now, in detail. Ask for the type of food, whether it is flake, pellet, granule, or wafer, and what size it is, because a pellet that suited a larger tankmate may be too big for the fish you are buying. Ask whether the food floats, sinks slowly, or drops straight to the floor, and where in the water column the fish usually takes it. Ask whether the shop also offers frozen or live foods, which ones, and on which days, because a fish conditioned to expect frozen food several times a week may treat a dry-only menu as a poor substitute at first. Ask how long the fish has been on that diet, and whether the shop feeds one staple or rotates several foods.
The Routine: Amount, Timing, and Competition
Ask how many times a day the fish is fed, roughly how much is offered, and whether the shop builds in a fasting day. Ask who reaches the food first in the display tank, because a slow fish housed with bold tankmates may have been underfed without looking thin yet, while a confident feeder usually settles faster at home. Ask whether this individual fish comes up eagerly at feeding time or hangs back, and how long it has been feeding in the shop, since a fish that has eaten well there for a settled period has already proved it can cope with captivity. Write the answers down at the counter, because details like a second small evening feed are exactly the details that vanish by the time you are acclimating the bag at home.
Bring the Old Food Home With the Fish
Buy a small supply of the same food the shop uses, even if you intend to feed something different long term. Feed the familiar food alone on arrival day, so the fish meets one new thing at a time: your water first, your menu later. The next morning, start the nine-day blend. For the first three days, offer mostly the old food with a little of your new staple mixed in. For the next three days, offer the two in roughly equal amounts. For the final three days, offer mostly the new staple with a little of the old food, and feed the new staple alone once those nine days are complete and the fish is eating confidently. If the fish refuses the mixture on any day, step back to the previous ratio for two more days rather than pushing forward, and never let a changeover become a hunger test for a fish that is still settling.
Reading the First Fortnight Honestly
Watch how the fish feeds, not just whether food disappears, because bold tankmates can clear a meal while a new fish gets nothing. If a fish that ate well in the shop refuses everything for several days in your tank, test the water first, check that the temperature matches what it came from, and phone the shop or an aquatic vet with the diet history you recorded rather than guessing. That written history, food, timing, appetite, and the stage of the blend, is what turns a vague worry into a conversation someone can actually help with. KinsLe's Care Teams keeps the nine-day blend on track in a shared home by assigning each feed to a named person, so the ratios change on schedule instead of by whoever remembers.