Tank Setup & Volume
Rectangular Volume
Calculate gallons/liters for standard tanks.
Bowfront Volume
Exact volume for curved glass aquariums.
Cylinder Volume
Round, hexagon, and biOrb tank volumes.
Sump Volume
Calculate water volume in your sump/filter.
Substrate Calculator
How much sand/gravel do you need?
Glass Thickness
Safe glass thickness for DIY builds.
Equipment & Hardware
Heater Size
Wattage needed for your target temp.
Filter Flow Rate
Required GPH/LPH for your livestock.
Filter Media
How much ceramic media you need.
Chiller Sizing
BTU/HP needed to cool your tank.
Lighting (Lumens)
Total lumens needed for plants.
PAR Depth
Light penetration at substrate.
LED Coverage
How many fixtures to cover your tank.
UV Sterilizer
Wattage and flow rate for sterilization.
RO/DI Waste
Calculate waste water ratio.
Electricity Cost
Monthly power bill estimate.
Water Chemistry & Dosing
Water Conditioner
Dechlorinator dosage for water changes.
Medication Dosage
Safe dosing for sick fish.
Ammonia for Cycle
Dose ammonia to start the nitrogen cycle.
Water Change
Gallons to change to lower nitrates.
GH/KH Converter
Convert dKH to ppm and mg/L.
CO2 Calculator
Dissolved CO2 via pH and KH.
EI Dosing
Dry fertilizer macros and micros.
Reef & Saltwater
The Ultimate Aquarium Calculation Hub
Welcome to EinstApp, the most comprehensive suite of online aquarium calculators. Whether you are setting up your first freshwater betta tank, managing a high-tech planted aquascape, or maintaining a sensitive SPS reef aquarium, math is the foundation of success.
Our tools are designed to be lightning-fast, mobile-friendly, and scientifically accurate. Stop guessing your water volume or fertilizer dosages. Click any tool above to get instant, precise results that will keep your aquatic life thriving and your water parameters stable.