Aquarium Stocking Calculator

Check freshwater fish compatibility, water conditions, group requirements and tank-size suitability before adding fish to an aquarium.

Aquarium Stocking Calculator

Tank Size

Press Enter to apply tank volume and refresh analysis when fish are selected.

Add Fish

  • Neon Tetra

    Paracheirodon innesi

  • Guppy

    Poecilia reticulata

  • Betta

    Betta splendens

  • Peppered Corydoras

    Hoplisoma paleatum

  • Harlequin Rasbora

    Trigonostigma heteromorpha

  • Zebra Danio

    Danio rerio

  • Platy

    Xiphophorus maculatus

  • Molly

    Poecilia sphenops

  • Honey Gourami

    Trichogaster chuna

  • Cherry Barb

    Puntius titteya

Your Aquarium

0 species

No fish selected yet. Search and add a fish to begin.

Aquarium Results

Add fish and click Analyze Aquarium to show all six compatibility checks.
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Detailed Analysis

Temperature Analysis

Selected species need a shared comfortable temperature range.

Result

Temperature has not been analysed yet.

What this means

Add fish and click Analyze Aquarium.

pH Analysis

pH describes how acidic or alkaline the water is.

Result

pH has not been analysed yet.

What this means

Add fish and click Analyze Aquarium.

GH / Water Hardness Analysis

General Hardness (GH) represents dissolved minerals, especially calcium and magnesium.

Result

GH has not been analysed yet.

What this means

Add fish and click Analyze Aquarium.

Social / Group Analysis

Some species need a verified minimum group. A preferred group is guidance only and is not a tank stocking limit.

Result

Social / group has not been analysed yet.

What this means

Add fish and click Analyze Aquarium.

Species Compatibility

Matching water needs does not guarantee that fish will get along. Behavior is checked separately.

Result

Species compatibility has not been analysed yet.

What this means

Add fish and click Analyze Aquarium.

Tank Size Analysis

Minimum tank requirements are species-specific planning guidance, not a guarantee.

Result

Tank size has not been analysed yet.

What this means

Add fish and click Analyze Aquarium.

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Information & Resources

Calculator results are planning guidance, not a guarantee. Individual fish and aquarium conditions vary. Review all checks and verify important stocking decisions with additional reliable sources. Users remain responsible for their animals, equipment, and aquarium decisions. AquaScience is not responsible for losses, injury, livestock death, equipment damage, water damage, or other consequences arising from reliance on calculator output. Read full disclaimer.

How to Use This Calculator

  1. Enter your aquarium volume in litres or gallons.
  2. Search for freshwater fish by common or scientific name.
  3. Add each species you want to compare.
  4. Adjust quantities using the + and - controls.
  5. Click Analyze Aquarium to run all six checks.
  6. Read every check together before making stocking decisions.

Need a quick overview first? Visit the Freshwater Aquarium Tools homepage.

What AquaScience Checks

  • TemperatureSelected species should share an overlapping temperature range.
  • pHSelected species should have compatible, overlapping pH ranges.
  • GH / Water HardnessFish can prefer different dissolved mineral levels, so GH ranges are checked separately.
  • Social / GroupSchooling and social fish may need minimum group sizes where verified data exists.
  • Behavioral CompatibilityKnown pair-level behavior risks are checked separately from water compatibility.
  • Tank Size SuitabilityYour entered aquarium volume is compared with stored minimum species requirements.

Why All Six Checks Matter

Two fish can match on temperature or pH and still have problems in the same aquarium. Group needs, behavior, GH/water hardness, and tank size can change the result.

How to Read Your Results

Compatible / Suitable

No known problem found by that specific check.

Needs Attention / Caution

Something should be reviewed before stocking.

Conflict / Incompatible

The selected setup fails that specific check.

Not Enough Data / Info

A reliable conclusion cannot currently be made.

A green result in one category does not guarantee the full aquarium plan is safe. Review all six checks together.

Limitations of the Calculator

This calculator is planning guidance based on available data. It cannot account for every individual fish temperament, aquarium layout, health condition, territorial situation, or unusual environment. Use the results with species-level research and real-world observation.

Helpful Equipment (Coming Soon)

Future updates will include practical equipment suggestions linked to your results.

  • Water testing basics
  • Heating and temperature monitoring
  • Filtration and flow support

Stocking Calculator FAQ

How does the Aquarium Stocking Calculator work?▼

It runs six separate checks: temperature, pH, GH/water hardness, social/group needs, behavioral compatibility, and minimum tank size.

Can this calculator tell me exactly how many fish I can keep?▼

No. It is a planning tool for compatibility and minimum tank-size checks, not an exact fish-count calculator.

Does fish compatibility depend only on tank size?▼

No. Fish can still conflict because of water needs, social/group requirements, or behavior even when tank size is large enough.

Why can one compatibility check pass while another fail?▼

Each check measures a different risk. Review all six results together before deciding on a stocking plan.

What happens when AquaScience does not have enough data?▼

That section shows Not Enough Data / Info so you can research the missing part before stocking.

Does the calculator check schooling requirements?▼

Yes. The Social / Group check compares selected quantity against stored minimum group requirements where verified data exists.

Does the calculator check fish behavior?▼

Yes. Behavioral compatibility is checked separately using known pair-level behavior records.

Can freshwater fish with different pH needs live together?▼

Sometimes, if their acceptable pH ranges overlap. If ranges do not overlap, the pH check will show a conflict.

Is this calculator a replacement for researching each species?▼

No. Use it as a practical planning step, then review species care details before making final stocking choices.