Aquarium Calculators

Essential tools for freshwater and saltwater aquarium hobbyists. Calculate tank volume, fish stocking levels, equipment sizing, water parameters, and maintenance schedules for healthy, thriving aquatic environments.

Aquarium Calculators

Browse aquarium calculators for tank volume, stocking, filtration, dosing, and fish care planning.

aquarium calculatorsaquarium calculator categoryfish tank calculators

Aquarium Air Pump Size Calculator

Estimate aquarium air pump airflow, outlet count, and reserve aeration margin from tank size, depth, stocking, and device load.

aquarium air pump size calculatorwhat size air pump do i need for aquariumfish tank air pump calculator

CO2 Drop Checker Color Guide Calculator

Interpret drop checker color with pH and KH to estimate aquarium CO2 ppm, compare against planted-tank targets, and spot fish-stress risk.

CO2 drop checker calculatordrop checker color guidewhat does my drop checker color mean

Calcium & Alkalinity Demand Calculator

Estimate reef tank calcium and alkalinity demand, starting two-part doses, and kalkwasser equivalents from coral load and chemistry targets.

calcium alkalinity demand calculatorreef two-part dosing calculatorreef calcium calculator

Carbon Dosing Calculator

Estimate starting carbon dose, weekly ramping, oxygen risk, and nitrate reduction timing for reef tanks using vodka, vinegar, sugar, or NoPox-style products.

carbon dosing calculatorvodka dosing reef tank calculatorhow much vodka to add to reef tank

Aquarium CO2 Injection Calculator

Calculate optimal CO2 injection rates for planted aquariums. Get bubble rate recommendations, estimate cylinder duration, and calculate CO2 levels from pH and KH readings.

aquarium CO2 calculatorCO2 injection calculatorplanted tank CO2

Drip Acclimation Timer Calculator

Calculate drip acclimation time, final dilution volume, discard water, and safety guidance for aquarium fish, corals, and invertebrates.

drip acclimation calculatorhow long to drip acclimate fishaquarium acclimation timer

Fish Stocking Order Planner

Plan the order to add aquarium fish using tank-type rules, aggression ranking, conflict warnings, and a staged stocking timeline.

fish stocking order calculatorwhat order to add fish to aquariumaquarium stocking order planner

KH/GH Hardness Calculator

Calculate aquarium KH or GH dose requirements using baking soda, buffers, Equilibrium, crushed coral, or Epsom salt with split-dose guidance.

aquarium KH calculatorGH hardness calculatorhow to raise KH in aquarium

Aquarium Filter Flow Rate Calculator

Calculate optimal aquarium filter flow rate in GPH/LPH based on tank volume, stocking level, and tank type for proper filtration and water quality.

aquarium filter calculatorfilter flow rate calculatorGPH calculator

Nitrate & Phosphate Dilution Calculator

Calculate how many water changes are needed to lower aquarium nitrate or phosphate, including refill-water effects and correction timeline planning.

nitrate dilution calculatorphosphate dilution calculatorhow many water changes to lower nitrate

Aquarium Fertilizer Dosing Calculator

Calculate optimal fertilizer doses for planted aquariums using EI, PPS-Pro, or lean dosing methods with NPK and micronutrient targets.

aquarium fertilizer calculatorEI dosing calculatorplanted tank fertilizer

Aquarium Heater Size Calculator

Calculate the right wattage aquarium heater based on tank volume, room temperature, and target temperature with single and dual heater recommendations.

aquarium heater calculatorfish tank heater sizeheater wattage calculator

Aquarium Lighting Calculator

Calculate optimal aquarium lighting intensity in lumens and watts for planted, fish-only, or reef tanks with PAR estimates and photoperiod recommendations.

aquarium lighting calculatorplanted tank lightPAR calculator

Aquarium Medication Dosing Calculator

Calculate accurate aquarium medication doses based on actual water volume with adjustments for sensitive species and re-dosing guidance.

aquarium medication calculatorfish medication dosingich treatment calculator

Aquarium Nitrogen Cycle Calculator

Track aquarium nitrogen cycle progress with test readings, calculate fishless cycle ammonia dosing, and estimate when your tank is ready for fish.

nitrogen cycle calculatoraquarium cycling calculatorfishless cycle calculator

Ozone Dosing Calculator

Estimate reef ozone starting dose, ORP-based adjustment, safety zone, and time-to-target from total system volume and ozonizer capacity.

aquarium ozone dosing calculatorhow much ozone for reef tankreef ozone calculator

Aquarium Evaporation Rate Calculator

Calculate daily aquarium water evaporation based on surface area, temperature, humidity, and tank type. Plan ATO reservoir sizing and understand salinity impact.

aquarium evaporation calculatortank evaporation rateATO sizing calculator

Aquarium Salt Mix Calculator

Calculate the amount of marine salt needed for your target salinity. Perfect for water changes, new tank setup, and maintaining optimal salinity in reef and marine aquariums.

salt mix calculatormarine salt calculatorreef tank salinity

Specific Gravity & Salinity Converter

Convert aquarium specific gravity, ppt salinity, and refractometer readings with temperature correction and reef-safe interpretation.

aquarium specific gravity to salinity convertersaltwater aquarium salinity calculatorspecific gravity converter

Aquarium Ammonia Toxicity Calculator

Calculate actual toxic ammonia (NH3) from total ammonia readings based on pH and temperature. Determine danger levels and when emergency action is needed.

ammonia toxicity calculatorNH3 calculatoraquarium ammonia

Aquarium Chiller Sizing Calculator

Estimate aquarium chiller BTU load, horsepower recommendation, and monthly operating cost from system size, room temperature, and equipment heat.

aquarium chiller sizing calculatorwhat size aquarium chiller do I needaquarium chiller BTU calculator

Aquarium Electricity Cost Calculator

Estimate monthly and annual aquarium electricity cost from heaters, pumps, skimmers, lights, and support equipment with a device-level breakdown.

aquarium electricity cost calculatorhow much does it cost to run an aquariumreef tank electricity bill

Aquarium Substrate Calculator

Calculate exact aquarium substrate amounts in pounds and kilograms for gravel, sand, or planted substrates based on tank dimensions and desired depth.

aquarium substrate calculatorgravel calculatoraquarium sand calculator

Aquarium Tank Volume Calculator

Calculate aquarium water volume in gallons and liters for rectangular, cylindrical, bow front, and hexagonal tanks with displacement estimates and equipment recommendations.

aquarium volume calculatortank volume calculatorfish tank gallons

Aquarium Temperature Adjustment Calculator

Estimate safe aquarium temperature change timing, heater adequacy, and total time to target from volume, wattage, and room conditions.

aquarium temperature adjustment calculatorhow fast can I change aquarium temperatureaquarium heater temperature calculator

Aquarium Water Change Calculator

Calculate optimal water change volume and frequency based on tank size, nitrate levels, and stocking density for healthy aquarium maintenance.

aquarium water change calculatorfish tank water changehow much water to change

Aquarium Fish Stocking Calculator

Calculate safe fish stocking levels for your aquarium based on tank volume, species bio-load, and filtration capacity with multi-species support and schooling warnings.

fish stocking calculatorhow many fish in tankaquarium stocking calculator

Aquarium Fish Compatibility Calculator

Check fish compatibility before adding new species to your aquarium. Analyze temperament, water parameters, tank size requirements, and potential conflicts between fish species.

fish compatibility calculatoraquarium fish compatibilityfish tank compatibility

Aquarium Breeding Tank Calculator

Calculate optimal breeding tank setup for your fish species. Get recommendations for tank size, water parameters, spawning conditions, and fry rearing requirements.

breeding tank calculatorfish breeding setupspawning tank size

Aquarium Quarantine Tank Calculator

Calculate quarantine tank requirements for new fish, sick fish treatment, and disease prevention. Get tank size, equipment, and medication dosing recommendations.

quarantine tank calculatorQT tank setupfish quarantine guide

Quarantine Medication Schedule Calculator

Build a quarantine medication timeline for ich, velvet, brooklynella, bacterial infection, or flukes with dose planning, daily tests, and fallow guidance.

quarantine medication schedule calculatoraquarium ich treatment schedulefish quarantine medication calculator

Aquarium Protein Skimmer Calculator

Calculate the right protein skimmer size for your marine aquarium based on tank volume, bioload, and system type. Get air draw and pump recommendations.

protein skimmer calculatorskimmer sizingreef tank skimmer

Aquarium Refugium/Sump Calculator

Design and size your sump and refugium. Calculate section dimensions, flow rates, and return pump requirements for optimal reef tank filtration.

refugium calculatorsump sizingsump design

Aquarium Water Flow Calculator

Calculate optimal water flow and circulation for your aquarium. Get recommendations for powerhead placement, return pump sizing, and turnover rates for reef and freshwater tanks.

water flow calculatoraquarium circulationpowerhead calculator

Sump Return Pump Sizing Calculator

Estimate sump return pump flow at real installed head using turnover target, pipe size, head height, and fitting friction.

sump return pump sizing calculatorwhat size return pump for sumpaquarium return pump GPH calculator

Reverse Osmosis Waste Water Calculator

Estimate RO and RO/DI waste water, waste ratio, total feed water, product TDS, and water cost for aquarium purification.

ro waste water calculator aquariumhow much waste water does RO produceRO water waste ratio calculator aquarium

Bioload & Oxygen Demand Calculator

Estimate fish oxygen demand from biomass, temperature, and agitation to check whether an aquarium has a safe oxygen margin.

aquarium bioload oxygen calculatorhow much oxygen do aquarium fish needaquarium oxygen demand

Live Rock Quantity Calculator

Estimate how many pounds of live rock, dry rock, or ceramic structure your aquarium needs based on tank size and aquascape density.

live rock quantity calculatorhow much live rock per gallondry rock calculator reef tank

pH Buffer & pH Adjustment Calculator

Estimate a safe daily buffer dose to raise aquarium pH while accounting for KH and avoiding overly fast correction.

ph buffer calculator aquariumhow much buffer to raise aquarium pHaquarium ph adjustment calculator

Saltwater Aquarium Magnesium Calculator

Estimate how much magnesium supplement to add to a reef tank and spread the correction across safe daily dosing steps.

aquarium magnesium calculatorreef tank magnesium dosing calculatorhow much magnesium to add reef tank

Coral Growth Rate & Frag Yield Calculator

Project coral growth and likely frag yield from coral type, frag count, time horizon, calcium, alkalinity stability, and lighting quality.

coral growth rate calculatorfrag yield calculator reef tankSPS growth calculator

Planted Tank CO2 Demand Calculator

Estimate planted-tank CO2 demand, target pH, starting bubble rate, and rough cylinder duration from tank size, pH, KH, and lighting demand.

planted tank co2 demand calculatorhow many bubbles per second co2 planted tankplanted tank co2 injection calculator

UV Sterilizer Sizing Calculator

Estimate aquarium UV sterilizer wattage, max effective flow, and exposure effectiveness for algae, bacteria, or protozoa treatment goals.

aquarium UV sterilizer calculatorwhat size UV sterilizer do I needuv sterilizer sizing calculator

Pond Volume Calculator

Estimate pond gallons, liters, baseline pump sizing, filter capacity, and conservative fish counts from pond shape and depth.

pond volume calculatorhow many gallons is my pondpond gallons calculator

Reef Tank Two-Part Dosing Calculator

Estimate reef correction doses, maintenance dosing, and monthly cost for two-part calcium and alkalinity supplementation.

reef tank two part dosing calculatorhow much two part to add reef tankreef calcium dose calculator

Stocking Level Inch-Per-Gallon Calculator

Estimate aquarium stocking percentage with an improved inch-per-gallon model adjusted for tank type, filtration, substrate, and species bioload.

inch per gallon rule aquarium calculatorhow many fish can I put in my tankaquarium stocking level calculator

About Aquarium Calculators

Professional Fishkeeping Tools

Our aquarium calculators provide accurate measurements for tank volume, fish stocking, equipment sizing, and water chemistry to help you maintain healthy aquatic ecosystems.

For All Aquarium Types

Whether you're setting up a freshwater community tank, planted aquarium, reef system, or fish-only marine tank, these tools support proper planning and ongoing maintenance.

Key Features

  • Multiple tank shape support
  • Displacement calculations
  • Equipment recommendations
  • Metric and imperial units