What is the effect of low PH levels


New member
Jul 4, 2010

I have an open air pool in Spain and though I have had it for four years know almost nothing about pools - other than how to clean them.

The sand in my filter needs replacing, but I have put off doing it because I need to have some work done to replace tiles and a crack where the pool meets the patio.

Last week the chorline levels were low, even though there are still some tablets in the dispenser. So I put extra chorline in the pool.

This week the PH levels are very low. I will get some PH plus tomorrow, but in the meantime I would like to know what the effect is of low, or high, PH levels. I only have a simple test kit which shows four levels, it is on the lowest one.


LifeTime Supporter
May 23, 2007
Montreal Canada
Putting aside the chemistry and water balance aspects, the low pH could possibly damage a liner by causing wrinkles, hardening and elongation. This is partly due to the acid dissolving the calcium carbonate used as a filler in PVC formulations. Elongation then allows the disinfectant to further penetrate the membrane possibly leading to discoloration.