TankStockingFreshwater aquarium planner
Stock your aquarium with confidence.
Tell TankStocking your tank size and the fish you like. Get an instant, honest verdict on whether they'll actually thrive together — before you spend a penny or risk a life.
Stocking Planner
Add your fish and tank size, get an instant compatibility + stocking-level verdict with the reasons spelled out.
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Volume Calculator
Work out how many gallons (and litres) your tank really holds — then send it straight to the planner.
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How it works
The exact model behind the verdicts: bio-load, hard welfare blockers, plant handling, data sources and limits.
Open →Why TankStocking
The stocking calculator the hobby actually deserves
🌱 Planted-tank aware
The old tools flag a healthy planted tank as "overstocked". TankStocking doesn't make that mistake — without ever relaxing the checks that actually protect fish.
🛟 Welfare-first, not a single %
A clear verdict — Good / Caution / Not recommended — with the specific reasons listed. Tank too small, school too small, temperature clash, aggression, fin-nipping, predation.
🔍 Transparent & sourced
Every species figure is sourced and dated (v2026.06). We publish the full model — no black box.
📱 Fast & shareable
Works instantly on your phone. One tap copies a share link or a forum-ready summary of your build.
Frequently asked
Is TankStocking free?
Yes — every tool is free and works in your browser with no account or sign-up.
How is this different from AqAdvisor?
TankStocking is built for modern phones and browsers, accounts for planted tanks instead of flagging them as overstocked, leads with clear welfare warnings rather than a single percentage, and publishes exactly how it works with dated, sourced species data.
Does it cover saltwater or reef tanks?
Not yet — TankStocking focuses on doing freshwater really well. A reef/saltwater mode is on the roadmap.
Will the planner tell me my fish are 100% safe?
No tool can promise that. TankStocking gives a conservative planning estimate and flags risks; you still need to cycle the tank, test your water, and observe your fish.
Plan it before you buy it.
Sixty seconds in the planner can save a fish's life and your money.