Hi VinnyinNJ: Chlorine use in a hot tub is great. I use it in my own hot tub. The reason that Aqua Clarity works so well with chlorine or bromine is that it helps to prevent biofilms from attaching to surfaces even when those levels may be depleted for short periods. Chlorine and bromine oxidize or “burn out” planktonic or “free-floating” biofilm cells but once they attach and colonize or grow into the sticky slime forming gunk in your plumbing, chlorine and bromine really can’t remove them. Sanitizers, chlorine or bromine, try hard to break into the biofilm outer layers but get used up trying without any success, When little bits or pieces of the gunk breaks loose from the host family, if there is a residual or sanitizer in the water, it gets removed. Unfortunately, many hot tubs or swim spas can be operated with very low or zero sanitizer during heavy use times which allows biofilms to stick and grow. This can occur quickly, especially if the tub is shut off soon after the soak. Aqua Clarity MUST be used with chlorine or bromine or any EPA Registered sanitizer for best results. Aqua Clarity is NOT a product that can be used without chlorine or bromine as the main sanitizer. Aqua Clarity will be your backup quarterback when sanitizer levels get depleted and bacteria from bathers is allowed to fester in the tub. Aqua Clarity will aid as a water clarifier because the gunk that would normally begin to colonize inside your plumbing and jets is now transferred to your filter(s). As your filter(s) accumulate bio-gunk the water going through the filter(s) slows down and has a harder time permeating through the pleats, allowing for finer filtration. Yes, you will need to rinse the filters more often. However, it is simple to do that and remember the best news, you won’t need to purge the tub nearly as often since biofilm formations will be greatly mitigated By the use of Aqua Clarity. Using only one ounce weekly for each 200 gallons of water is all you need. The 6 ounce bottle of concentrate is diluted with 122 ounces of tap water to make a gallon. Be sure to use a good quality gallon jug, (not included), that has a child resistant cap for safety. Do not use a milk or water jug. You need a gallon jug that has a #2 in the recycling triangle at the bottom. One bottle of Aqua Clarity treats a 400 gallon hot tub weekly and provides two (12 ounce) purges for one whole year. At $89.95 this is a fantastic product and price.