Guppy fry are born ready. Unlike egg-layer young that live off a yolk sac for days, newborn guppies swim and hunt within hours of birth, and their growth in the first week is set almost entirely by two things: food small enough to fit their mouths, offered often enough to keep their tiny stomachs working. Get the size and the frequency right and the fry grow visibly day by day; get either wrong and they stall in water that is quietly fouling from the food they could not eat.
What to feed: small, protein-rich, varied
A newborn guppy's mouth takes in food measured in crumbs, so everything must be powdered or alive and minute. Finely crushed flake rubbed between your fingers to dust is the staple most keepers already own, and powdered fry food does the same job more evenly. Live foods are the growth accelerant: newly hatched baby brine shrimp are small enough from birth, wriggle in a way that triggers hunting, and are rich in the protein fry are building bodies from. Microworms and vinegar eels suit the first days for the smallest fry in a batch. A practical rotation is powdered food for most meals and a live meal once or twice a day; variety now also makes fry less fussy feeders as adults.
How often: four to five small meals a day
A fry's stomach is roughly the size of its eye, empties fast, and the fry burns energy constantly just staying in the water column. Four to five small meals spread across the waking day — roughly every three to four hours — suits the first week far better than two large ones. Judge the amount by the two-minute rule: offer a pinch that disappears within a couple of minutes, leaving bellies looking gently rounded, never bulging, and no film of leftovers settling on the bottom. If food is still drifting after five minutes, the next meal gets smaller. From the second week you can ease toward three or four meals as mouths and stomachs grow.
Water: the other half of feeding
Frequent feeding in a fry tank, breeder box or small rearing tank pollutes quickly, and in the first week water quality matters as much as the menu. Siphon the bottom gently each day with airline tubing to lift waste without lifting fry, and replace small amounts of water often rather than making one large change — always with water matched for temperature. Keep filtration gentle: a sponge filter feeds almost nothing into the current, gives fry a surface to graze microorganisms from, and cannot trap them the way an intake can. Warm, stable water in the range adults enjoy, kept steady, supports appetite and digestion.
Reading the fry, and sharing the schedule
Healthy first-week fry are active, spread through the water rather than clamped at the surface, with full-looking bellies after feeds and steady, even growth across most of the batch — a few runts are normal in any drop. Fry that hang at the surface, refuse powdered food repeatedly, or stop growing are telling you to test the water and add a live-food meal before changing anything else. Five feeds a day is a schedule few single keepers can hold alone for a week, which is where sharing helps: KinsLe's Care Teams lets you assign each fry feed to whoever is home as a dated duty, and every completed feed is timestamped, so the midday meal is never skipped in assumption or doubled in kindness.