Reef Water Tracker

My tank:

Tank size

Length (cm)Width (cm)Depth (cm)

Sump or extra water (litres)Or enter total litres (optional)

Working volume is an estimate. It uses a flat 10% allowance for rock and sand and does not account for the water actually displaced by your rock, substrate and equipment. If you know your real system volume, enter it as total litres. Your tank settings are saved on this device. Choose the coral group above to match your tank. Ranges come from the Reef Coral Guide.

Tank parameters

Test date

Parameter	Your reading	Ideal	Tolerated	Status

Ideal is where to aim. Tolerated is what the coral can survive for short periods, so a reading outside it is flagged as extreme. Stability matters more than hitting exact numbers: avoid swings in alkalinity of more than 1 dKH per day, and in temperature of more than 1 °C per day.

What to do, in order of priority

My log

Saved on this device only. With two or more entries, the tracker estimates how fast alkalinity, calcium and magnesium are used.