Guide
Great setups for a 40 gallon community tank
Larger tanks mean bigger schools and more variety. Example combinations that work.
- 40 gallons suits multiple schools, centrepiece(s), and a solid cleanup crew.
- Match species to water hardness and temperament; avoid mixing fin nippers with long-finned fish.
- Strong filtration and regular water changes; cycle first and stock gradually.
Setup 1: Three schools
10–12 neon or cardinal tetras, 10–12 harlequin rasboras, 8–10 corydoras, 1–2 dwarf gouramis or a pair of rams. Strong filtration and weekly water changes.
Setup 2: Angelfish community
2 angelfish, 12–15 rummynose or cardinal tetras (avoid very small nippable species), 8 corydoras. Tall tank preferred for angels. Plenty of plants and vertical space.
Setup 3: Rainbowfish and friends
6–8 rainbowfish (e.g. Boeseman's or dwarf neon), 10–12 tetras or rasboras, 8 corydoras. Rainbows need hard water; match other species to your water parameters.
Setup 4: Mixed peaceful
8 black neon tetras, 8 cherry barbs, 8 platies, 8 corydoras, 1 bristlenose pleco or nerite snails. Lots of colour and activity without aggression.
General tips
40 gallons gives room for larger schools and a more impressive display. Still respect bioload and compatibility. Canister or dual HOB filtration often works well. Cycle thoroughly and add fish in groups. Log water parameters 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: Three schools?
10–12 neon or cardinal tetras, 10–12 harlequin rasboras, 8–10 corydoras , 1–2 dwarf gouramis or a pair of rams. Strong filtration and weekly water changes.
Setup 2: Angelfish community?
2 angelfish, 12–15 rummynose or cardinal tetras (avoid very small nippable species), 8 corydoras. Tall tank preferred for angels. Plenty of plants and vertical space.
Setup 3: Rainbowfish and friends?
6–8 rainbowfish (e.g. Boeseman's or dwarf neon), 10–12 tetras or rasboras, 8 corydoras. Rainbows need hard water; match other species to your water parameters .
Setup 4: Mixed peaceful?
8 black neon tetras, 8 cherry barbs, 8 platies , 8 corydoras, 1 bristlenose pleco or nerite snails. Lots of colour and activity without aggression.
General tips?
40 gallons gives room for larger schools and a more impressive display. Still respect bioload and compatibility . Canister or dual HOB filtration often works well. Cycle thoroughly and add fish in groups. Log water parameters in App-aquatic .
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