Great setups for a 20 gallon community tank

Setup 1: Classic tetra and cory

6–8 neon or cardinal tetras, 6 corydoras, 1 dwarf gourami or honey gourami. Heater, HOB or small canister, and weekly water changes. Simple and colourful.

Setup 2: Betta community

1 betta, 6–8 small rasboras (e.g. harlequin or chili), 6 corydoras. Plenty of plants and hiding spots. See betta tank mates and neon tetras with betta for compatibility.

Setup 3: Livebearer tank

6 guppies or platies, 4–6 corydoras, optional nerite snails. They breed; plan for fry or have a plan for offspring.

Setup 4: Peaceful variety

6 zebra danios or white cloud minnows, 6 harlequin rasboras, 4–6 corydoras. Active, hardy, and easy to care for.

General tips

Keep schools of at least 6 for schooling species. Add fish gradually and cycle first. Track water parameters and avoid overstocking. Log tests in App-aquatic.

Quick takeaways

• 20 gallons suits one or two schools plus centrepiece and bottom dwellers.
• Stick to peaceful, similar-sized fish and proper group sizes.
• Cycle first, add gradually, and keep up with water changes.