Hot tub chemistry calculator

PRO

Bromine or dichlor dose for a spa.

Inputs

Result

Dichlor
0.04 oz
Sodium bromide
0.04 oz

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The formula

Dichlor oz = (gal/10k) × 0.23 × ppm. Bromine similar (× 0.25).

Worked example

400 gal × 4 ppm dichlor = 0.04 oz (~1 gram).

Frequently asked

Bromine vs chlorine?

Bromine handles hot water better and irritates less.