4,473 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.
713 answers in Home & Lifestyle — page 11 of 30
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…
Sand or smooth, rounded gravel suits a bristlenose pleco best, because this fish spends nearly its whole life in contact with the floor — grazing across it, resting on it, and shuffling over it after dark. Sharp gravel can scrape the soft underside and mouth as the pleco works a patch, so texture matters more here…
Smooth fine sand or rounded fine gravel suits a betta best, because a betta often rests low in the tank and drags long, delicate fins across the floor. Fine grains also trap less uneaten food than chunky gravel, which matters in the small, warm tanks bettas usually live in. A natural, darker colour helps a betta's own…
Fine sand or smooth, fine gravel suits an angelfish tank best, laid deep enough to root the tall plants angelfish like to drift between. Angelfish feed mostly in open water, so the substrate serves the plants, the bottom-dwelling tank mates, and the look of the tank more than the angels themselves. A darker, natural…
A group of white cloud mountain minnows needs at least a 10-gallon tank, and a 20-gallon long is a better home for an active school of eight or more. These slim, cool-water fish stay small but swim constantly through the middle and upper water, so a longer footprint matters more than extra height. Pick the larger…
A threadfin rainbowfish needs at least a 20-gallon long tank for a proper school. Males carry long, delicate trailing fins and display to each other constantly, so the school needs swimming length plus gentle flow that will not batter those fins. Keep eight to ten or more, plant the back and ends, and leave the centre…
A sparkling gourami needs at least a 10-gallon tank for a pair or small group, and a 15- to 20-gallon suits a group with several males better. These tiny croaking gouramis are peaceful overall, but males spar over plant-thick corners, so floor space divided by planting keeps the peace. Still water, floating cover, and…
A scarlet badis needs at least a 10-gallon tank for a pair or trio, with a 20-gallon long better if you want more than one male. These thumbnail-sized hunters are territorial, and each male needs his own plant-choked patch to claim. Dense planting, caves, and leaf litter break the tank into separate territories and…
A rummy-nose tetra school needs at least a 20-gallon long tank, and a 30-gallon or larger is better for the dozen-plus fish that show their famous tight schooling. Their red noses and black-and-white tails only shine when they can travel together down a length of open water. Keep the group large, the water clean and…
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