Pools get cloudy for many reasons like bacteria growth, chemistry imbalance, high total dissolved solids, and particulate in the water. This only works on particulate, and generally only benefits those of us with sand or cartridge filters. DE filters can filter out the particulate by themselves. Particulate can form for several reasons like a dust storm or what most of us have had, algae that we have otherwise killed. That's the big one. Your effect of using this product on an algae bloom is going to be minimal at best until after you've killed it off. Your green pool kinda goes white after you've killed the algae, and it is too small to be caught in your sand or cartridge filter, so it passes through. What this product does very well is to attract those particles together in larger clumps that are either too big to pass through the filter or heavy enough that they fall to the bottom where they can be vacuumed up and out. Two methods [in both cases, shock your pool till the green is gone and clean your filter first]: 1) This is really the only method Robarb tells you about. It works most of the time when the pool is just a bit hazy, but you can easily still see 6 ft down. Adjust your pH as necessary to between 7.2-7.6. Pour just a few ounces based on directions for your pool volume into the skimmer so it disburses through the circulation system. Otherwise, it is too thick and it can sink to the bottom or just not circulate well. Let the pump run nonstop until it clears up, often by the next day. Backwash your filter. 2) This is for when you've had a big mess and the one that Robarb doesn't tell you about. It's too complicated to put on the back of a bottle. Do back to back shocks and blind sweep the floor and walls to make algae come loose, and do this until there is no more green. After the algae is dead, it turns white and makes the pool very cloudy. Raise your water level to the top of the skimmer because you'll lose water in the last phase of cleanup. Double check your pH to see that it is in the correct range of 7.2-7.6, and adjust as necessary. Dump 1 qt Robarb per 10,000 gallons through the skimmer, and let this circulate for 2 hours. Then turn the pump off and leave it off for between 24-48 hours. Don't even think about turning it on because it will disrupt the entire process. Don't brush the pool, go into the pool, or even think about the pool. Not following this instruction is where 90% of the screwups happen. If you are moving, you're disrupting the process of particles floccing together and settling to the bottom. After your water is clear, you have to get this dead stuff off the bottom. Set your valve or whatever your system allows to allow you to vacuum to waste and set up your vac carefully so as to cause minimal disruption at the bottom of the pool. Only after this has been done can you turn on the pump. Water will be exiting your pool so start quickly. Use continuous side to side motions to vacuum the bottom of your pool. All that dead algae will be taken to waste instead of through your filter. Trying to run it through your filter to save water often doesn't work, and you don't want to have to do this a second time on the same dead algae. I've seen people try and it usually doesn't work the second round. After you've vacuumed the pool, return your filter to the normal operating position and run the pump for 24 hours to get rid of the last of the haze. If it still seems fairly hazy, you can facilitate the cleanup process by adding a couple of ounces to the skimmer as in #1 above. And yes, I consulted on a lot of pool service for about 22 years from small above ground residential pools to commercial and city double Olympic size, and have seen hundreds of people per year go through the process. Do it right and it's 100% effective. If it's not effective, you either misdiagnosed the problem, didn't read all the instructions here or just didn't do it right, even if you're sure you did.
