Tools & Calculators
Every build decision, one calculator away - brand-agnostic, no signup.
Every calculator here runs on your own tank's numbers, not a generic rule of thumb, and picks no brand winner by default. Start with the Tank Volume Calculator if you don't already know your true water volume after rock and sand displacement.
Tank Actual Water Volume Calculator
Find your true water volume after sand and rock displacement.
Water ChemistryAlkalinity & Calcium Dosing Calculator
Get a safe, ramped two-part dosing schedule for your tank.
LivestockLivestock Compatibility Checker
Check any two species before you add them to the same tank.
EquipmentProtein Skimmer Size Calculator
Find the right rated capacity for your tank volume and bioload.
EquipmentReturn Pump GPH Calculator
Get a rated-GPH target that accounts for vertical lift and elbow head loss.
EquipmentSump Size Calculator
Get a minimum and target sump size before you factor in skimmer and refugium space.
EquipmentReef Lighting PAR Calculator
Target PAR range by coral type, at coral placement depth.
EquipmentPowerhead Flow Rate Calculator
Total system flow by coral demand, minus what your return pump already provides.
EquipmentPlumbing Pipe Diameter Calculator
Minimum Schedule 40 pipe size for your target flow, gravity drain or pressurized.
LivestockStocking Calculator by Tank Size
A rough bioload read by fish size tier, far more conservative than freshwater rules.
TroubleshootingReef Tank Problem Identifier
Describe what you're seeing, get pointed to the right ID and treatment guide.