I converted our pool to the BBB from Baqa-goo last year with great sucess. Opened up this year around mid-April and had no issues until late spring. I kept getting these dirt buildups on the creases on our liner and a light film all over the floor and the water never was completely clear, always a slight cloudy-ness. It didn't seem like it was alge, my numbers were perfect every night, so I chalked it up to pollen since it was so bad this year. I'd brush, vacuum to waste and next day it would be back. Added DE, got skimmer socks hoping they would catch the fine particles and again, no luck. Then come July 4 my pool turned into a green mess. Again my numbers were fine, just this bright green water. To say I was discouraged was an understatment. I was having baqa-goo flashbacks. I even in a moment of desperation bought some HTH alge remover or whatever it's called and a packet of super shock (which did make a slight improvement but not great). I kept thinking it had something to do with the sand in my filter and thought maybe I needed to put one of those chemical cleaners in there, but alas I stumbled on a post that seemed to be the same problem I was having. So hubby took the top off of the filter to expose the sand and we gently poked it around, drained some of the green goo water out and backwashed for 5 minutes. Day by day it's cleared up and last night I could see the bottom perfect, could see if a coin was heads or tails if it was in there. Did a vacuum last night (regular not to waste) and as of this am, still perfectly clear. 
This was the first winter we didn't change our sand, we always thought you had to change each year but the pool store actually told me you didn't . So I was skeptical and on the verge of changing sand next.
The skimmer socks (another thing I started to use from being on this site) are much cleaner when I check on the skimmer and I'll still will use them, they help cut down on some of the bugs and nasties that get past the skimmer. I hate taking the lid off of the "pot" or whatever that's called. Well I hate trying to get the lid back on more than anything.
So thank you to this site for helping me once again
This was the first winter we didn't change our sand, we always thought you had to change each year but the pool store actually told me you didn't . So I was skeptical and on the verge of changing sand next.
The skimmer socks (another thing I started to use from being on this site) are much cleaner when I check on the skimmer and I'll still will use them, they help cut down on some of the bugs and nasties that get past the skimmer. I hate taking the lid off of the "pot" or whatever that's called. Well I hate trying to get the lid back on more than anything.
So thank you to this site for helping me once again
