Can't Get PH to go Up

[smsprague]

I am having trouble getting my PH to increase. The current level is 6.8 (Using a Taylor Test kit) and I have added 60 oz of Soda ASH over the last two days and it has not moved up at all. My other readings are:

DE Filter
Gunite 18K Gallon pool

PH 6.8
TA 140 PPM
CYA 90 PPM
FC 8 PPM

I am currently using a Chlorine Puck feeder. I am going to switch to a SWG (AutoPilot) this weekend but want my water to be in-line before doing it.

Any ideas?

 

[JasonLion]

Trichlor pucks will constantly lower the PH. You are probably only adding enough PH Up to compensate for the pucks. You should keep adding PH up to get the PH to at least 7.0. Once you switch to the SWG the behavior of the PH will change, probably tending to go up instead of down.

 

[JohnT]

The reading of 6.8 really means no higher than 6.8. It could be lower, and you are increasing, but still not over 6.8. Try adding soda ash to a bucket of pool water until you get a change. You can then extrapolate the amount it took from the bucket volume to the pool volume and get a rough idea how much you will use to get the pool to move.