Hi all -
I bought a house with a 20 y/o in ground plaster pool in November 2022. its 12,500 gal with an attached spa, in-line chlorinator, Pentair variable speed pump, Master Temp heater, and and cartridge filter. It has a waterfall, but we never turn it on. The spa has an air blower, but we never turn it on.
When I bought the house, the pool was fine, but plaster was needing a resurface. At that time, the chemical levels stayed pretty consistent. In March 2023, I had it replastered with plain white plaster. Since then, I can't get the ph in check. I go through 16 oz of 31% muriatic acid every 1-2 days now - 19 months after the replaster. My other chemical levels are pretty stable.
Here is my last readings:
Free chlorine: 3.1
Total chlorine: 3.1
PH 8.1. (I usually lower it to 7.2-7.4)
Alk 57
Ca Hardness 387
CYA 48
Copper 0.1
Iron 0.0
I use Leslie's 3" jumbo tricolor tabs in the chlorinator - not more than 2 at a time. It runs through them every 2-3 weeks.
When the chlorine level is super low, I shock it with Leslie's Power Powder - 1 x 1lb bag.
Last spring/early summer, I added 13 boxes of 20-mule team borax...and a lot of muriatic acid. I was hoping that would help stabilize ph, but it seems to have made it just require more acid for any ph adjustment. 16 ounces of acid now gives me only a 0.2-0.3 ph drop. I've played with the alkalinity range, but the ph creep happens the same whether alkalinity is in the 50s or the 100s.
I keep the pool pretty clean - no trees overhead, and I manually vacuum or run the Polaris robot at least once weekly. I run the pump enough to cycle the pool about 3 times per day.
I assume the plaster is cause of the ph rise, since it was stable before the replaster, but I'm surprised to still be dealing with it after so long. Any ideas?
I bought a house with a 20 y/o in ground plaster pool in November 2022. its 12,500 gal with an attached spa, in-line chlorinator, Pentair variable speed pump, Master Temp heater, and and cartridge filter. It has a waterfall, but we never turn it on. The spa has an air blower, but we never turn it on.
When I bought the house, the pool was fine, but plaster was needing a resurface. At that time, the chemical levels stayed pretty consistent. In March 2023, I had it replastered with plain white plaster. Since then, I can't get the ph in check. I go through 16 oz of 31% muriatic acid every 1-2 days now - 19 months after the replaster. My other chemical levels are pretty stable.
Here is my last readings:
Free chlorine: 3.1
Total chlorine: 3.1
PH 8.1. (I usually lower it to 7.2-7.4)
Alk 57
Ca Hardness 387
CYA 48
Copper 0.1
Iron 0.0
I use Leslie's 3" jumbo tricolor tabs in the chlorinator - not more than 2 at a time. It runs through them every 2-3 weeks.
When the chlorine level is super low, I shock it with Leslie's Power Powder - 1 x 1lb bag.
Last spring/early summer, I added 13 boxes of 20-mule team borax...and a lot of muriatic acid. I was hoping that would help stabilize ph, but it seems to have made it just require more acid for any ph adjustment. 16 ounces of acid now gives me only a 0.2-0.3 ph drop. I've played with the alkalinity range, but the ph creep happens the same whether alkalinity is in the 50s or the 100s.
I keep the pool pretty clean - no trees overhead, and I manually vacuum or run the Polaris robot at least once weekly. I run the pump enough to cycle the pool about 3 times per day.
I assume the plaster is cause of the ph rise, since it was stable before the replaster, but I'm surprised to still be dealing with it after so long. Any ideas?
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