Guppies & Tropical Fish

Key Stats at a Glance

Overview

Guppies (Poecilia reticulata) are among the most popular tropical fish in the hobby. Originally from South America, they come in a rainbow of colours and fin shapes. They are livebearers — females give birth to live fry rather than laying eggs — and breed prolifically. Guppies thrive in community tanks with similarly peaceful, small fish.

Tank Setup

• •A 40–60 litre planted aquarium is ideal for a group of 6–10 guppies.
• •Use a gentle sponge filter — guppy fry are tiny and can be sucked into strong filter intakes.
• •Maintain 22–28°C with a reliable aquarium heater.
• •Dense plantings (Java moss, hornwort, water wisteria) provide hiding spots for fry and reduce aggression.
• •Avoid keeping guppies with fin-nipping species such as tiger barbs or serpae tetras.
• •A 20–30% water change weekly keeps the tank in top condition.

Breeding

• •Guppies are livebearers — females give birth to 20–60 live fry every 4–6 weeks.
• •Maintain a 2:1 female-to-male ratio to reduce stress on females.
• •A separate breeding tank or dense plant cover allows fry to survive without being eaten.
• •Feed fry baby brine shrimp, micro worms, or crushed flakes for the first few weeks.
• •Separate males and females if you want to control breeding.

Water Parameters

• •Guppies prefer slightly hard water — add crushed coral or limestone rock if your tap water is very soft.
• •Ammonia and nitrite must always be zero; nitrate should be kept below 20 ppm.
• •Test water parameters weekly, especially in a newly set-up tank.
• •Avoid sudden temperature changes — even a few degrees can cause stress and ich.
• •Use a quality water conditioner to remove chlorine and chloramine from tap water.

Health Tips

• •Ich (white spot) is the most common guppy disease — raise temperature to 28–30°C and treat with ich medication.
• •Wasting disease (or "guppy disease") causes fish to appear bent or swim erratically; maintain clean water and quarantine affected fish.
• •Fin rot starts at fin edges with fraying or discolouration — treat with aquarium-safe antibiotics and improve water quality.
• •Quarantine all new fish for 2 weeks before adding to a community tank.

Compatible Species