Aquarium Calculators
& Science Tools
15 free tools built on real aquarium science. Water chemistry, stocking, filtration, disease treatment, lighting, and more. No account required, no paywalls.
Water Quality
Water Parameters
Look up ideal water parameter ranges for any freshwater species. Compare pH, GH, KH, temperature, and nitrate thresholds across species.
Nitrogen Cycle
Track your tank's nitrogen cycle progress. Input ammonia and nitrite readings to assess where you are in the cycle and what to do next.
Water Change
Calculate exact volumes to remove, predict nitrate concentration after each change, and determine how many changes are needed to reach your target nitrate level.
Filter Size
Calculate required filter flow rate based on tank volume, stocking level, and species bioload. Get specific canister, HOB, sponge, and sump model recommendations.
Stocking & Compatibility
Stocking Density
Calculate safe stocking levels for your tank. Accounts for tank volume, filtration, fish bioload, and species-specific space requirements.
Compatibility Checker
Evaluate whether two species can safely share a tank. Analyzes water parameter overlap, temperament, size disparity, and dietary compatibility.
Chemistry
pH Buffer
Calculate how much pH buffer (sodium bicarbonate, crushed coral, peat, etc.) to add to raise or lower your tank's pH to a target value.
GH/KH Converter
Convert between dGH, dKH, ppm (mg/L CaCO₃), and mmol/L. Includes carbonate hardness buffering guide and species GH/KH reference table.
Salt Dosage
Calculate precise salt doses for freshwater disease treatment, electrolyte support, brackish water preparation, and marine saltwater mixing with SG presets.
Medication
Calculate precise doses for kanamycin, metronidazole, copper, ich treatments, and praziquantel. Generates treatment schedules with water change timing and species safety warnings.
Utility
Tank Volume
Calculate the true water volume of any tank shape — rectangle, cylinder, hex, bowfront, corner, and L-shaped tanks. Accounts for substrate and equipment displacement.
Temperature Converter
Convert aquarium temperatures between Fahrenheit and Celsius. Includes species-specific ideal temperature reference table.
Feeding Calculator
Calculate correct daily feeding amounts based on fish count, species type, and food form. Prevents overfeeding — the leading cause of aquarium water quality issues.
Heater Size
Calculate the correct wattage for your tank, room environment, and species requirements. Includes model recommendations, dual heater guidance, and monthly energy cost.
Lighting
Calculate PAR requirements for your plants. Convert between PAR, lux, and lumens. Get fixture recommendations for low, medium, and high-light planted tanks with CO₂ interaction analysis.
Need a complete tank design?
The AI Tank Blueprint Generator combines all of these tools into a single, complete tank setup plan. Input your goals — get a full stocking list, parameters, plants, and maintenance schedule.
Generate AI Blueprint