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.
649 answers in Home & Lifestyle — page 8 of 28
Move angelfish in sturdy bags or a lidded container of their own tank water, kept dark and at a stable warm temperature, and never transport them in the aquarium itself. Stop feeding a day ahead so the travel water stays cleaner, set the destination tank up and running before you catch anyone, and acclimate slowly on…
This is the one goldfish pairing that can sometimes work, with strict conditions. Zebra danios tolerate the cooler water goldfish need and are too quick to be easily caught, but they may nip the fins of slow fancy goldfish and will outcompete them for food, so the mix suits only large tanks with fast, single-tailed…
No, goldfish and kuhli loaches should not share a tank. Kuhli loaches are slender warm-water bottom dwellers that need sand, cover, and a settled group, while goldfish need cooler water, stir the substrate constantly, and can mouth or swallow a small loach as they grow. Keep kuhlis in a heated, sandy tank of their…
No, goldfish and harlequin rasboras should not live in the same tank. Harlequin rasboras are small tropical schoolers that need warm water and can be mouthed or eaten by a growing goldfish, while goldfish need cooler water and will outcompete the school at feeding time. Keep rasboras in a heated community tank and…
No, goldfish and guppies cannot live together safely. Guppies are small warm-water livebearers that fit the pattern of food to a growing goldfish, their long-finned males invite mouthing, and any fry born in the tank will be eaten quickly, while goldfish water is too cold for guppies to thrive. Keep guppies in their…
No, goldfish and corydoras should not share a tank as a planned pairing. Corydoras are small warm-water catfish that a growing goldfish may try to swallow, and their stiff fin spines can lodge dangerously if that happens, while the goldfish's cooler water and heavy waste suit the corys poorly. Keep corys in a heated…
Generally no, goldfish and bristlenose plecos should not share a tank, even though both look peaceful in the shop. Bristlenose plecos are warm-water fish that can rasp at a goldfish's slime coat as it rests, while goldfish need cooler water and produce waste loads that foul the pleco's bottom territory. Choose a…
No, goldfish and angelfish should not live in the same tank, because their basic needs point in opposite directions. Goldfish are cold-water fish that produce heavy waste and grow large, while angelfish are warm-water fish with delicate trailing fins that a curious goldfish may nip and that suffer in cooler, dirtier…
This pairing is possible but genuinely risky, so it is not a first-choice mix. Zebra danios are fast, restless surface swimmers that prefer slightly cooler, moving water, while angelfish are slow, tall-finned fish that like calm warmth and may be nipped or stressed by constant danio activity. If you try it, use a long…
Yes, angelfish and kuhli loaches are one of the safest pairings you can choose, because the loaches live on the bottom and come out mostly at dusk while angelfish occupy the middle and top. Give the kuhlis soft sand, caves, and a group of their own kind so they feel secure enough to forage. Through KinsLe Family…
Yes, angelfish and harlequin rasboras usually live together safely, because rasboras are peaceful, deeper-bodied schoolers that are harder for an angelfish to treat as food than tiny slim tetras. Keep the rasboras in a proper school, add them while the angelfish are still young, and give the tank height, plants, and…
Yes, angelfish and corydoras are a classic, peaceful pairing, because the corys shoal along the bottom in their own busy group while the angels hold the middle levels. The safety points are practical: keep corys in a group of six or more on smooth sand, feed sinking food the angels cannot intercept, and choose adult…
Yes, angelfish and bristlenose plecos are one of the more reliable pairings in a community tank, because the pleco works the bottom and glass at night while the angels cruise the middle in daylight. Safety depends on space and food reaching the bottom, since a hungry pleco can rasp at any fish's slime coat and angels…
Smooth, rounded gravel or sand suits zebra danios well, since these fast surface swimmers barely use the bottom but still need a floor that will not trap waste or scratch any tankmates below them. A darker fine gravel shows off their striping and anchors plants along the back, while an open layout leaves them the long…
Smooth sand or fine, rounded gravel suits siamese algae eaters best, because these active grazers work along the bottom and rest on surfaces, and sharp grains can irritate their mouths and undersides. Choose a floor that still anchors plants, since they also graze leaves, and vacuum open areas regularly where their…
Fine, dark sand or smooth, fine gravel suits pearl gouramis best, because it supports rooted plants, feels natural under a shy fish, and will not snag fins during low-level exploring. Keep the layer deep enough for plant roots, rinse it thoroughly before it goes in, and vacuum it gently so waste is lifted without…
Dark fine sand or dark fine gravel suits neon tetras best, recreating the dim, leaf-bottomed streams they come from and making the electric blue-green stripe and red tail glow by contrast. Neons school in mid-water, so the substrate works through light and plants: a dark bed absorbs glare that would keep the school…
Sand or smooth fine gravel suits mystery snails, giving their broad soft foot a gentle surface to glide over and a bed they can push into for a shallow rest. Sand keeps the generous waste and uneaten food these large snails produce visible for siphoning, while fine gravel offers more grip and hides debris between…
Soft, fine sand is the substrate kuhli loaches need — they burrow into the bed until only their heads show, dive into it when startled, and sift it for food with delicate barbels and scaleless skin. Gravel blocks all of that: a kuhli on gravel can neither dig nor feed naturally, and sharp edges can damage skin that…
Dark fine sand or fine gravel suits harlequin rasboras best, echoing the leaf-stained forest streams they come from and setting off the copper-orange body and black wedge they are kept for. These are mid-water schooling fish, so the bed works indirectly: it anchors the plants they school around, tones down reflected…
Fine gravel or sand suits guppies well, in a layer deep enough to root the floating and stem plants a guppy tank depends on. Guppies are adaptable about the floor itself, but newborn fry drop toward cover near the bottom, and fine grains with dense low planting give them hiding texture that coarse, gappy gravel does…
Sand or smooth stones too large for a goldfish to fit in its mouth suit a goldfish tank; a thin layer of either, or even a bare floor, beats standard aquarium gravel here. Goldfish constantly mouth the substrate while foraging, and ordinary pea gravel is exactly the size to lodge in a goldfish's throat. Sand passes…
Soft, fine sand is the substrate that suits corydoras, full stop — these catfish feed by pushing their snouts into the bed and sifting it, and they explore the world through the sensitive barbels around the mouth. Coarse or sharp gravel wears those barbels down and blocks the sifting behaviour entirely, leaving the…
Dark fine sand or fine gravel suits cherry barbs best, because males show their deepest red over a darker floor and the whole school forages and displays close to the bottom among plants. Fine grains root the dense planting these shy fish use for cover, and they hold scattered food where the barbs can pick it up…
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