Water change and nitrate calculator

How much water to change and how far each change will lower your nitrates.

Tank volume

Change percentage

Current nitrate (mg/l)

mg/l

Nitrate in new water (mg/l)

mg/l

Target nitrate (mg/l)

mg/l

Water to change60 l

Nitrate after the change29.5 mg/l

To reach the targetA 57 % change114 l

How it’s calculated

Calculated by dilution: new water replaces old water in the same proportion. Several small changes lower nitrate with less stress on the fish than one big one.