Family: Poeciliidae
A vividly colored, prolific livebearer — the classic beginner fish in endless fancy strains.
The guppy is the gateway fish of the hobby — abundant color, live-bearing convenience, and endless strains. Given clean water and steady warmth, it multiplies happily.
Yes — they're one of the most forgiving starter fish, tolerating 18–28 °C and a wide range of conditions. The two real pitfalls are jumping (always use a lid) and overpopulation: one pair can become dozens within half a year.
They're livebearers — females give birth to free-swimming fry every 28–35 days once mature, with 20–60 fry per brood. To control numbers, keep an all-male group or isolate pregnant females in a breeder box.
Males are smaller (~3.5 cm) with large colorful tails; females reach 5 cm with round bellies and plain coloration. A 30 L tank suits 4–6 fish — try 1 male to 2 females, or all males. Overcrowding causes fin rot and oxygen stress.
Usually ammonia or poor water quality; sometimes nipping. Change a third of the water, improve filtration, and hold 26 °C steady. Methylene blue or a fin-rot medication helps in serious cases — once rot reaches the tail base, recovery is unlikely.
They're omnivores: flakes, granules, brine shrimp and bloodworms all work. Feed small amounts often — 1–2 minutes' worth once or twice daily for adults, and newly hatched brine shrimp 2–3 times a day for fry.
Separate them immediately — mothers eat their own young. Feed baby brine shrimp for the first week, hold 26–28 °C with stable water, and do small daily water changes instead of running a filter. You can sex them at about 2 months.
They survive above 18 °C but become lethargic and ich-prone below 20 °C long-term. In unheated rooms, a heater set to 24–26 °C makes a visible difference in health and color.
Peaceful tetras, corydoras and small plecos. Avoid bettas, tiger barbs and large characins — fancy guppy tails are irresistible targets. Live plants sharply improve fry survival.
Typically 1.5–2 years, up to 2.5 with excellent care. They breed so readily that the colony outlives individuals — keeping guppies is really keeping a population.
They prefer moderately hard water (GH 9–19) and slightly alkaline pH (7.0–8.0), matching their Trinidadian floodplain origins. In soft-water regions, a little crushed coral raises GH and improves fry development.