Hi all,
I have a 35k gallon vinyl pool.
I have struggled with a white powder deposit on the bottom and in the corners.
I test my chems regularly and have them confirmed once a week at the pool store. This past week, they said it was very good with a slightly high CYA, but not actionable level.
Every so often I get this white powder. Water is crystal clear except for the deposits at the bottom. They brush into a cloud.
I shocked twice with cal hypo and when I do the water clouds up, then clears with more powder at the bottom.
I've vacuumed to my ctg filter, cleaned and even replaced the ctgs. This process reduces the powder and then I used an Algaecide 60 and it seemed completely gone.
Some time goes by and I see tiny powder remnants. I brush and check chems. And then twice now it spreads a lot on the floor.
I feel like I'm fighting and constantly killing algae and then it gets away from me. Or is it the calcium hypo dust? Or something else?
Water is so clear, but can't completely rid of this powder problem.


I have a 35k gallon vinyl pool.
I have struggled with a white powder deposit on the bottom and in the corners.
I test my chems regularly and have them confirmed once a week at the pool store. This past week, they said it was very good with a slightly high CYA, but not actionable level.
Every so often I get this white powder. Water is crystal clear except for the deposits at the bottom. They brush into a cloud.
I shocked twice with cal hypo and when I do the water clouds up, then clears with more powder at the bottom.
I've vacuumed to my ctg filter, cleaned and even replaced the ctgs. This process reduces the powder and then I used an Algaecide 60 and it seemed completely gone.
Some time goes by and I see tiny powder remnants. I brush and check chems. And then twice now it spreads a lot on the floor.
I feel like I'm fighting and constantly killing algae and then it gets away from me. Or is it the calcium hypo dust? Or something else?
Water is so clear, but can't completely rid of this powder problem.


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