Hi, we are new to the BBB method. I have been coming to TFP for advice for a year or two and decided to take the plunge (and hopefully control of our old pool) this season.
We started out with an initial algae bloom in late March, and followed the advice for "Turning Your Green Swamp Back Into a Sparkling Oasis" and it worked great within two or three days - turning the milky blue within 24 hrs and filtering out after that.
As you can see from the test results, we have an obvious problem with CYA thanks to eight years of pool store chemicals and adding "optimizer" at their suggestion. A couple of weeks ago, we decided to do a drain and replace in hopes of lowering the CYA. We drained a little over half the pool and refilled. Unfortunately, we now have two problems...the CYA is still reading 100+, and since we did not want to pour chlorine in the pool just to drain it into the yard we have another algae bloom. The unseasonably warm April/May in the southeast has not helped.
Last Friday, we started the process to get rid of the algae using the method from this site that seems to work for everyone else, and worked for us once. Assuming the CYA was 100, we brought the FC level to 39 (which worked for us in March) and kept it there through the weekend. Because the pool never turned the milky blue color, we have been bringing the FC level back up to 39 twice a day (morning and evening). We are not seeing a lot of movement between readings (the lowest the FC has been in the past week is 32).
The problem is, the pool is still green - it never turned the milky blue. The algae seems to be dead, it is settling on the bottom, but the general color of the pool is still green. We are not seeing a pressure increase or a lot of algae when we are backwashing - it just seems that everything is still in the pool. Is it possible that the algae is dead even though it appears green?
I told my DH that while he vacuums the pool in hopes of speeding up the filtering process, I would pose the question to the experts. After eight years of fighting it, if this pool doesn't become "trouble free" soon he might lose it.