Bio-Active BA-CAR-08 Non Polluting 100-Percent Cyanuric Acid Reducer Powder for Commercial and Residential Swimming Pools, 8 Ounces.

Worked as expected – will need another bag though, have just a bit more to go before I reach the right number. When I purchased, my CYA was around 300 or more (lets put it this way, I was way passed the 100 mark on the tube) – I have a 10k and the bag says it will treat up to 25k … well, I am now at 100. So, it works, but you may need more than one bag depending on size of pool and amount of CYA in pool. Also you should note that it can take up to 10 days to lower your levels – so I will have to wait another 6 days before adding a second bag to be sure.Leslie’s charges $49.95, so this is a good price.Now, this wasn’t the only thing wrong with my levels, so how it worked for me, may not be what you need (and I suppose I won’t really know if it works until I add the second bag and see if it drops to where it needs to be)How I did it :I took out my chlorine duck and let the pool do it’s thing (running 8 hours a day) for about 10 days with no chems.Then I washed my filters thoroughly and added the Phos Killer (from walmart $9 – kills 1000 ppm) and ran the pool for 48 hours non stopThen I turned the system off for 24 hours and let the pool sitAfter 24 hours I washed my filters again and then added my duck back into the pool and let the pool run a normal cycle for another day before FINALLY adding the whole bag of CYA into the skimmer and let the pool run normal cycles for 72 hours before adding the Alkaline Up – then ran it for 12 hours and when I took my water to be tested everything was back to normal except I’m now at a 100 on my CYA rather than 300, so if after 6 more days the levels aren’t where they need to be, I think one more bag should do itThis is the information I was given about using the Bio-Active product:::Bio-Active uses natural cultures to reduce your CYA, be sure your pool will be habitable for the the organisms to do their job. You should also not that your chlorine will attack these organisms, so it’s best to be in normal or low ranges. In addition to providing livable ranges for the active ingredient to thrive in, make sure you take note of the information below to get the most out of each dosage:» Do not add shock or algaecides 7 days prior to application.» Works best in an outdoor pool, uncovered for at least 7 days.» Bio-Active does not work in mineral system pools.» Make sure your pool is free of algae or other contaminants.» Be sure to shut off UV, ozone, and chlorine feeders 15 minutes prior to, and 3 hours after, applying Bio-ActiveSafely lowers CYA levels within 10 days without needing to drain the pool.Eliminates chlorine lock due to high CYA.Use 1 bag for up to 25,000 gallons.Works best with water over 65 degrees Fahrenheit.I hope this helps anyone having troubles – I know it’s a bear of a situation and VERY time consuming …. Don’t you remember going to the lake and swimming or fishing, never once thinking of what microscopic things lay in wait? Having never once thought of PH levels or the like? We lived, didn’t get sick and kept going back (this is in no way meant to diminish anyone’s adverse reactions to such events – merely a personal reflection). Do you think lake or ocean water is cleaner than your pool? Yet here we all are, busting our hump, spending hours and hundreds of dollars even when our pools are sparkling clean and we can’t see anything wrong (as is my case – before all this process I mentioned, my water was clear, had no odor and looked great … but it had been a while since I’d had it professionally tested and wasn’t sure if MY test stuff was still optimal, so I took it in and BAM! There was evil lurking in that falsely serene setting of a sparkling pool ready for swimming. Sounds fishy to me, but – here I am, tired, annoyed, poorer and ready to just fill it in and plant grass!