No-Phos

No-Phos is a phosphate remover for hot tub and spa water. It chemically binds to dissolved phosphates in your water and drops them out of solution so your filter can catch them — removing the food source that lets algae grow and that burns through chlorine or bromine sanitizer faster than it should.

Why phosphates are a hidden problem in your water: Phosphates enter spa water from many sources — tap water (some municipalities add phosphate as corrosion inhibitor), well water, lawn fertilizer carried in on bare feet, body care products, even some scale-control chemicals. Once dissolved, phosphates feed any algae that finds the water and dramatically speed up consumption of chlorine and bromine. Salt water spas (Onzen, Spa Boy) are especially sensitive because phosphates can short out the salt cell's chlorine generation. If your sanitizer is disappearing faster than it should and you can't explain it, phosphates are the most common hidden cause.

How to use it: First test your phosphate level with a strip like AquaChek 1 Min Phosphate Test. If the reading is above 50 ppm, dose with No-Phos per the bottle directions, run the jets for 30 minutes to circulate, and let the spa run overnight. The phosphate-bound precipitate is captured by your filter — clean the filter the next day to remove the trapped material. Retest 24 hours after dosing to confirm levels have dropped.

Quick tips:

• Don't over-shock with bromine or chlorine while phosphate-treating — wait 24 hours after dosing No-Phos before adding shock, since they don't play well together
• If your fill water is consistently high in phosphates, treat at every fill rather than waiting for problems to develop