The planted tanks that stay peaceful are stocked by level and temperament, not by picking favourites one bag at a time. Plants change the equation in your favour — they break sightlines, soften light and give shy species cover — but they also rule out diggers and plant-eaters, and they reward fish that like the same soft, warm, gentle-flow water the plants do.
The Middle: One Proper School
Pick one schooling species and buy a real group, six at minimum and more if the tank allows. Ember tetras suit smaller aquariums and stay tiny; neon or cardinal tetras give the classic planted look in tanks from around twenty gallons; harlequin rasboras school tightly and are hardy for newer keepers. A group behaves completely differently from a pair — colours deepen, the school moves as one, and stress drops. Two rival half-groups of different tetras usually look messier and settle worse than one confident school, so commit to a species.
The Floor and the Glass
Small corydoras — pygmy, panda or bronze in larger tanks — work the substrate in a loose, social group and ignore everything above them. Keep them on smooth sand or fine rounded gravel, because coarse sharp substrate wears their barbels. For algae grazing, otocinclus are the planted tank's specialists: tiny, plant-safe and best in a group, though they need an established tank with real biofilm and should never be the first fish in. Nerite snails and small shrimp fill the remaining cleaning niches without troubling plants or fish.
The Top and the Centrepiece
A honey gourami makes a gentle centrepiece for smaller planted tanks, drifting through the upper level and leaving schooling fish alone. A single male betta can work in a calm community with no fin-nippers and no long-finned tankmates, but it is a gamble on individual temperament, not a default. Avoid the usual troublemakers: tiger barbs and other committed fin-nippers, larger cichlids that rearrange planting, goldfish of any kind, and big plecos that bulldoze aquascapes and outgrow community tanks entirely.
Match Water, Then Add in Stages
Most classic planted species share a comfort zone — warm water in the mid-seventies Fahrenheit, soft to moderately hard, with stable parameters mattering more than chasing an exact number. Test your tap water before shopping, because a species list built for soft water will sulk in liquid rock. Add fish to a fully cycled, already-planted tank in stages a week or two apart, floor and school first, centrepiece last, and quarantine new arrivals where you can — planted displays are miserable to medicate.
Before paying, get the shop to confirm adult sizes for your list, since several "community" fish are sold as juveniles of something much larger. Finding an aquatic shop whose staff keep planted tanks themselves, through KinsLe's Pet Services Directory, is the difference between a stocking list that lasts and one you are rehoming by spring.