Generally I have no problems with Ph, so this issue surprised me. I chlorinate using Kim-Tec liquid chlorine usually, or Up & Up brand bleach if I only get over to Target and not Lowe's. I also occasionally use Kim-tec brand tri-chlor if my CYA needs to be raised. I just started with using tricolor to raise my CYA again on Saturday. Since I only occasionally have to get my Ph down, I use Kim-tec brand Ph minus, as muriatic acid tends to sit around a long time before I get it all used used up - generally I will not go through a 2 gallon case in a season.
Anyway, I noticed my Ph was starting to creep. I measured 7.8 yesterday (actually more between 7.6 and 7.8), so I put in about 1/3 cup of Ph minus. Today I checked my Ph again, and it was 8.0!
I didn't add any other chemicals other than the Ph minus, and the tricolor my little floating dolphin tricolor dispenser is putting out. What would cause my Ph to go UP when I put in Ph DOWN?
Numbers from test yesterday (except chlorine and Ph, which was today):
TC = 3
CC = <.5 (This was yesterday; the test turned just barely pink, and went away with one drop. It was so light, I'm pretty sure if I could have used less than a drop that would have worked.)
FC = > 2.5
Ph = 8
T/A = 120
CH = 260
CYA = 30
Temp = 82