Natural Chemistry Pool Magic Spring & Fall + PhosFree, 1 Liter (33.9 oz), 05141

Pool Magic + PHOSfree is Natural Chemistry's season change product: an enzyme treatment and a phosphate remover in one 1 liter bottle, meant for the two points in the year when a pool carries the heaviest organic load.

What the enzymes do

The formula uses SMARTZyme technology. The enzymes bind to non living organic contaminants and break them into smaller and smaller parts, eventually down to carbon dioxide and water. Because each enzyme keeps working rather than being consumed, a small dose treats a large volume of water. That is what takes the grind out of an opening, and what keeps non living organic staining and phosphate build up from setting in over a closed winter.

How to dose it

For a new pool or an opening, balance and sanitize the water first, then shake the bottle well and add the whole thing to the skimmer with the filter running. Use one bottle for pools up to 25,000 gallons (95,000L) and run the pool normally for two weeks. At the end of that period, backwash or clean the filter and move to weekly maintenance with Pool Perfect + PHOSfree, provided your phosphates have come below 100ppb. For a closing, add the full bottle any time before you close, with the pump and filter running, then close as usual.

The bottle removes 300ppb of phosphates from 20,000 gallons (75,000L). If your fill water is high in phosphates, have it analyzed so the dose is matched to the problem.