Guide
Great setups for a 20 gallon community tank
Example combinations that work: schooling fish, centrepiece, and bottom dwellers.
- 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.
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.
Keep learning
Stable aquariums come from consistent testing and patient stocking. Continue with our water parameters guide, how to cycle a tank, and combining fish safely. For logging and strip scans, see App-aquatic.
Log parameters, scan strips offline, and run stocking checks with App-aquatic.
Get the free appSetup 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 .
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