I posted this information on another forum, but it seems to be pretty inactive (though the people there do seem quite knowledgeable).
Stats yesterday morning
Free Chlorine 5ppm
Total Chlorine 5ppm
Combined Chlorine 0ppm
Total Dissolved Solids 1500ppm
15,000 gallon in ground pool, plaster walls, sand filter. Water is cloudy white. Pump seems to move the water quite well when on and the pressure is about 10lbs after a backwash.
Last weekend the guy at the pool store sold me some clarifier and told me to put "this much" in the pool, "this much" being 16 oz. The instructions say to use 3 to 4 oz in a pool of my size on a weekly basis, so I figured that 16oz would be OK. But it got cloudier. About 4 days later with no improvement I decided to floc.
I brought a water sample to the pool store and got the numbers above. I was told to fix the harness first, so I added 10 pounds of Ram hardness control, let the filter run for 4 hours, and then added 12oz of pH plus to get the pH up to around 8. I let the pumps run for another 4 hours and then added 6 lbs of flocc. I set the timer to shut off the pump in 4 hours (as the instructions say) and let the pump run in whirlpool/recirculate (as the pool guy said to do). This was at about 7 PM last night. 12 hours later, the pool is cloudier than it was last night. I can no longer see the pool drain in the deep end (6ft). I think I'm supposed to wait 24 hours before vacuuming, but I was really hoping to see some results this morning.
If this is algae, will the flocc help? Can algae even make the pool water cloudy white? Should I have let the pump run longer? How obvious should the flocculated stuff be on the bottom of the pool? I just looked into the shallow end and saw a tiny amount of black stuff on the bottom, but my wife and I were doing some gardening yesterday and I suspect that it is likely just potting soil. I can actually see the 'stuff' floating in the water, it didn't seem to want to settle out like the pool store guy said it would so I set the filter to filter and let it run for a few hours until the pressure went up by about 3 PSI then I shut it down as I don't want it to run overnight right now.
Since I have 5ppm free chlorine and 0 combined chlorine, is it safe to assume that it isn't algae? Can algae even be white?