phosphates high? ph low

[CarlD]

Any CYA powder that's 100% Isocyanuric or cyanuric acid is fine.

The question isn't how much you should add, but what level of CYA do you desire. Usually, in a location like yours, something between 30 and 50 ppm is a good target.

[FormerBromineUser]

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An additional thought: Consider adding less CYA than you think you need so you don't overshoot your goal. You can always add more in a later if you need to. CYA levels don't naturally lower that much over time.

I undershoot with all my additions except chlorine. Call me over-cautious if you will...