Filter Flow Rate Calculator

GPH needed for tank volume with turnover rate target.

Tank Volume (gallons)

Tank Type

Stocking Level

Number of Filters

Tab to move between fields

Ideal Flow Rate (GPH)

180

Rated GPH to Buy

225

Minimum Flow Rate (GPH)120

Rated GPH per Filter225

Target Turnover (x/hr)6

Bio Media Needed (liters)3

How to Use This Calculator

How the result changes with Tank Volume (gallons)

Tank Volume (gallons): Total water volume of the aquarium in US gallons.
Tank Type: 1 = Freshwater community, 2 = Planted freshwater, 3 = Saltwater/Reef.
Stocking Level: 1 = Lightly stocked, 2 = Moderately stocked, 3 = Heavily stocked.
Number of Filters: How many filters you plan to use. Multiple filters provide redundancy.

Ideal Flow Rate (GPH): Recommended actual flow rate in gallons per hour for your setup.
Rated GPH to Buy: Filter rating to shop for (25% above ideal to account for head pressure and media resistance).
Minimum Flow Rate (GPH): Absolute minimum acceptable flow rate.
Rated GPH per Filter: Rating to look for per individual filter if using multiple.
Target Turnover (x/hr): How many times per hour the filter should cycle the tank.
Bio Media Needed (liters): Recommended volume of biological filter media (ceramic rings, bio-balls).

Identify Input Parameters
4 parameters
Tank Volume (gallons) = 30, Tank Type = 1, Stocking Level = 2, Number of Filters = 1 = 4 input(s) provided
Calculate Ideal Flow Rate
Ideal Flow Rate = tankVolume * adjustedIdealTurnover
180 = 180
Calculate Rated GPH to Buy
Rated GPH to Buy = idealGph * 1.25
225 = 225
Calculate Minimum Flow Rate
Minimum Flow Rate = tankVolume * adjustedMinTurnover
120 = 120
Calculate Rated GPH per Filter
Rated GPH per Filter = ratedGphNeeded / filterCount
225 = 225