Guppy

A 10-gallon tank is a reasonable minimum for a small group of guppies, and they need warm, heated water between 72 and 82 degrees F, with about 78 degrees F being ideal. Gentle filtration suits them well, and dense live or silk planting gives both adults and fry places to hide, which matters if you want any fry to survive to adulthood. A lid is a good idea since guppies can occasionally jump. They are peaceful community fish, but avoid pairing them with fin-nipping species, since a guppy's flowing tail is an easy target.

Guppies are omnivores that do well on a high-quality flake or micro-pellet food as their staple diet. Supplementing with frozen or live baby brine shrimp and daphnia adds valuable variety and encourages natural hunting behavior. Occasional spirulina-based flakes support healthy color. Feed small amounts once or twice a day. If you're intentionally raising fry, they need very fine food like infusoria, crushed flake, or baby brine shrimp until they're large enough for standard flake.

Guppies are strongly social schooling fish and do best in groups of six or more, ideally with two to three females for every male to reduce the stress of constant mating pursuit on individual females. They're active, colorful swimmers that appreciate a mix of open swimming space and planted cover. Their breeding behavior is itself a form of ongoing enrichment for the keeper to observe — from courtship displays to the birth of live fry — though a dedicated breeding box or heavily planted nursery area is needed if you want fry to survive, since adult guppies (including the mother) will readily eat them.

Fin rot from poor water quality and ich are the two most common issues. Because guppies breed so readily, overpopulation is a genuine and common problem — plan ahead for population control, whether that means separating sexes, accepting natural predation of fry, or having a rehoming plan in place. The bioload from a rapidly growing colony makes consistent water quality maintenance especially important; weekly 20 to 25 percent water changes help keep pace with a growing population.