3,895 answers about fish & aquatics
A healthy aquarium is a balanced one — water chemistry, filtration, stocking and feeding all work together, and most fish problems start with the water. This page gathers the fish and aquatics library of KinsLe Answers in one place, organized by topic for freshwater and saltwater keepers alike. Every answer is original, written by KinsLe, and tied to a real KinsLe feature.
297 answers in Young Pets — page 2 of 13
Young bristlenose plecos can move into the main tank once they are feeding independently away from their father's cave, grazing algae and taking prepared foods on their own, and are large enough — about an inch or more long — that other fish leave them alone. Adult bristlenose plecos rarely harm youngsters, so the…
Young angelfish can move in with adults when the deep part of the body, not counting fins, is clearly too wide to fit in an adult's mouth — roughly coin-sized across — and they are feeding boldly on their own. Move them sooner and adult angelfish may treat them as food; wait for steady growth and confident eating…
A healthy newborn zebra danio is tiny, almost transparent, and clings to glass or plants with a rounded yolk sac under its belly and dark, clearly formed eyes. Its spine looks straight, its body is clear rather than cloudy or fuzzy, and the yolk sac shrinks steadily over the first days instead of swelling. Expect it…
A healthy newborn pearl gourami is a dark-eyed speck that hangs in or just below its father's bubble nest, so small and translucent that the yolk sac and eyes are most of what you can see. It does not swim properly for its first days, drifting and righting itself near the surface, and a healthy one stays up in the…
A healthy newborn kuhli loach looks like a living thread: a pale, translucent, worm-like fry only a few millimetres long that makes straight for the substrate and disappears into fine sand or leaf litter. Its belly carries a small yolk sac at first, its barbels are tiny nubs, and the dark bands adults wear have not…
A healthy newborn harlequin rasbora is a glassy, hair-thin larva hanging beneath a leaf or against the glass, with a small neat yolk sac, prominent dark eyes, and almost no colour at all. The famous copper body and black wedge are entirely absent at birth and develop over the following weeks. As the sac is absorbed…
A healthy newborn guppy is born already swimming, uncurling within moments of delivery into a tiny, big-eyed fish that heads for the surface and can eat finely crushed food the same day. Its body is mostly translucent grey with a full-looking belly from the yolk it absorbed before birth, and it darts in quick,…
A healthy newborn goldfish is a nearly transparent sliver about as long as an eyelash, hanging on plants or glass while it finishes a small yolk sac, with two dark eyes that look far too big for its body. Once the sac is gone it swims level in short, wobbling darts, and its body stays straight with a belly that rounds…
A healthy newborn corydoras catfish looks like a miniature tadpole that has sunk straight to the bottom, with a rounded yolk sac, a plump little body, and the first whiskery barbels forming around its mouth. Within a day or two it starts making short, busy hops across the sand, resting between bursts, and its belly…
A healthy newborn bristlenose pleco is a tiny dark tadpole shape still inside or just outside its cave, carrying a large, smooth, orange-yellow yolk sac that makes its belly look comically round. The fry stay clustered near their father for days, wiggling rather than swimming, and the sac shrinks a little each day as…
A healthy newborn angelfish starts as a wriggler stuck head-up to the leaf or slate where it hatched, with a neat round yolk sac, dark eyes, and a constant fine trembling motion. Over the next several days the body straightens and the sac shrinks evenly, until the fry lets go and swims level with fins fanned and belly…
Baby zebra danios start on infusoria or liquid fry food as soon as they let go of the glass and swim free, because their first meals must be nearly microscopic. Within a few days they take powdered egg-layer fry food and microworms, and by the end of the first week most are snapping up freshly hatched baby brine…
Baby pearl gouramis are among the smallest common fry, so they begin on infusoria or liquid fry food for a full week or more after leaving the bubble nest. Only when they have grown visibly can they move to vinegar eels and microworms, and baby brine shrimp come later still, once their mouths are wide enough. Feed…
Baby kuhli loaches eat down at the bottom from the start, beginning with infusoria and microscopic life picked from plants and fine substrate once their yolk sac is gone. Within days they can work through microworms and finely powdered sinking fry food placed right where they hide, and later they manage small baby…
Baby harlequin rasboras eat almost nothing you can see at first, because newly hatched fry live off their yolk sac and then need microscopic infusoria or liquid fry food for several days. Once their mouths grow, they graduate to vinegar eels and microworms, then freshly hatched baby brine shrimp and finely powdered…
Baby guppies are born fully formed and swimming, so they eat from their first hours: finely crushed flake or powdered fry food dusted on the surface is an immediate staple. Newly hatched baby brine shrimp and microworms offered alongside make a visible difference to growth rate and early colour in the first weeks.…
Baby goldfish eat nothing for their first two days while they hang on plants and glass absorbing their yolk sacs, then need microscopic first foods — infusoria or liquid fry food — once they swim level and begin hunting. Newly hatched baby brine shrimp follow within days and drive the fastest growth, given several…
Baby corydoras catfish absorb their yolk sacs for the first couple of days, then need tiny live foods that reach the bottom where they live — microworms are the classic first food, sinking straight into the fry's world on the sand. Newly hatched baby brine shrimp and finely crumbled sinking fry food follow as mouths…
Baby bristlenose plecos eat their yolk sacs inside the cave for their first days under their father's guard, then emerge ready to graze biofilm and soft algae from driftwood, glass, and plant leaves. Offer blanched soft vegetables and crumbled algae wafers in the evening near the cave, since the fry feed most…
Baby angelfish eat nothing for their first days while they absorb their yolk sacs as wrigglers stuck to the spawning surface, then need microscopic foods once they swim free — infusoria and similar tiny live foods scattered where the cloud of fry hovers. Within days they graduate to newly hatched baby brine shrimp,…
A young zebra danio that is failing to thrive does the one thing healthy danios almost never do: it stops moving, hovering alone near the surface or behind the filter while the school races. Look also for thinning that makes the stripes sit on a pinched body, a developing spinal curve, clamped fins, and being left…
A young pearl gourami that is failing to thrive stays in cover through feeding, loses the bright pearl spotting and orange throat flush of a settling juvenile, and lets its long thread-like pelvic fins droop rather than sweeping them forward to taste its surroundings. Occasional trips to the surface for air are normal…
A young kuhli loach that is failing to thrive is hard to judge by hiding alone, since healthy youngsters hide all day, so look instead for a thin, dull body when it does emerge, worn barbels, and restless daytime looping up the glass that does not settle at dusk. A thriving juvenile is plump, glossy-banded, and…
A young harlequin rasbora that is failing to thrive breaks away from the school to hover alone near plants, loses its coppery flush so the black wedge shows against a washed-out body, and darts at food without actually taking it. Thinning behind the head, fins held tight, and a school that closes ranks without it are…
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