pH Calculator

Calculate how much muriatic acid or soda ash to add to adjust your pool pH.

Current Water Chemistry

Pool Volume (gallons) Don't know? Calculate it here

Current Total Alkalinity (ppm) Affects how much chemical is needed

Current pH

6.0 7.0 7.4-7.6 8.0 8.5

Target pH

7.2 Ideal Range 7.8

Ideal range: 7.4 - 7.6

pH Adjustment

Chemical Needed --

Amount to Add -- fl oz

Also equals --

Will change pH to --

Tip: Always add chemicals slowly with the pump running. Wait 30 minutes, then retest before adding more. pH naturally rises over time in most pools.

pH Chemicals Guide

To Lower pH (acid)

Muriatic Acid (31.45%) - Most common, effective, cheapest
Dry Acid (Sodium Bisulfate) - Easier to handle, more expensive

To Raise pH (base)

Soda Ash (Sodium Carbonate) - Raises pH and TA together
Borax - Raises pH with minimal TA impact
Aeration - Free! Run returns/spillover to off-gas CO2

Safety: Always add acid to water, never water to acid. Wear safety glasses and gloves when handling muriatic acid. Add in front of a return jet for better distribution.

pH & Chlorine Effectiveness

Lower pH = more effective chlorine. Here's why 7.4-7.6 is ideal:

pH	% HOCl (Active Chlorine)	Notes
6.0	97%	Too acidic - damages equipment
7.0	73%	Acceptable but low
7.2	63%	Good
7.4	52%	Ideal
7.6	40%	Ideal
7.8	30%	Acceptable but high
8.0	21%	Too high - chlorine ineffective

My Pool Settings