Hi, I'm sure I sound like a broken record but I have been reading for hours and am not sure what is going on with my pool. I started with a fresh fill this year after I put my new liner in around may. I have been on the BBB method for the first time and started when I filled the pool. I have been bringing my CYA up and working to get my TA down from over 250. Before I left for vacation I was at FC=2 PH=7.2 TA=150 CYA=25. While I was gone my mom was adding 12.5% Bleach and MA in the dosses that I told her to after she tested it every other day. She was adding a gallon off 12.5 bleach every other day because my pool is in full sun all day and the temps were over 105F every day I was gone the pool water was around 95 that whole week. The day I got home the FC went to 0 so I new something was up and gave it 2 Gal of 12.5% but I guess it was too late and it went green on me. I have been following the steps to cure it, but now I'm stumped. My pool water is greenish brown tint and has been for 2 days. Yesterday there was a lot of algae laying on the bottom so I vacced to waste then today there was just a little bit so I vacced to the filter but when I backwash the 250lb sand filter the sight glass stayed mostly clear. Here are my tests FC=12 CC=0 PH=7.8 CH=220 TA=110 CYA=25 Temp=92. I'm not sure why my glass stays pretty clear while back washing, why my CC is 0 and why my pool isn't getting clearer. Please help.
Another green pool after vacation
- Thread starter nathanc03
- Start date
Having CC of 0 is a good thing ... back to ABC's of Pool Water Chemistry 
How long are you backwashing?
Have you done the OCLT to see if something is still consuming your FC at night?
Although if the water is not clear, there is something in the water requiring you to continue the shock process.
You are going to loose a LOT of FC to the sun with a CYA that low, try bumping it up closer to 40ppm to start.
How long are you backwashing?
Have you done the OCLT to see if something is still consuming your FC at night?
Although if the water is not clear, there is something in the water requiring you to continue the shock process.
You are going to loose a LOT of FC to the sun with a CYA that low, try bumping it up closer to 40ppm to start.
I normally backwash until the water is clear which normally takes 30-45 sec but the past 2 time I probably back washed for 1min since the glass wasn't ever getting cloudy. I'm working on the CYA I don't want to get it too high so I have been adding stabilizer slowly. I'm going to get some liquid so tomorrow so I don't have to wait for the granular to dissolve. I will do the OCLT tonight. Thanks.
How often are you backwashing? Sand filters actually perform better when slightly dirty. If you backwash too often, you're doing more harm than good.
I was back washing once a day since the water wasn't clear, I will try every 3 days unless you suggest waiting even longer, just didn't want it to get clogged. I certainly didn't pass the OCLT 10:55PM FC=15 CC=.5 now 4:45AM FC=10.5 CC=.5 the chart shows I should be around 12 for shocking purposes so I'll add some more.
Try this....backwash after your pressure rises by 25% - take a look at your pressure gauge right after a backwash, that's your "clean pressure." If the "clean pressure" goes up by 25%, time to backwash.nathanc03 said: