I have a 2500 gallon indoor spa which gets no sun and I think using the 4 in 1 Suncoast Complete tablets is sky rocketing the cya, close to 300, skewing all tests. When I first filled it last year it took days to vacuum and filter out all the iron and mn that comes from my well. Since then, I have been using my neighbors well to add water.
First, will these tabs to do this? And why all of a sudden?
Second, how much of the water will I have to replace?
Third, If I want to spend some time putting water in pails, letting the minerals precipitate, then filtering it before it goes into the spa, how long should it take to precipitate in a pail? Or is this impossible?