Waskydiver presents a reasoned opinion. He might be telling my story. I joined this forum after using Baquacil for about seven years, the first four of which were trouble-free, the last three spent fighting algae and gummed up DE filter. Still, I was determined to hang with Baq because I travel on my job and find it difficult to keep up with maintenance. I was hoping to find some advice on how to deal with the continuing algae problems and the escalating cost of following the Baqucil dealers' and website advice. I found no one at all. You would think that at least one person, perhaps a casual web browser, on a widely visited website like TFP would have a good thing to say about the stuff. No chance! After two more years of pain and multiple unrequited pleas for a positive word, I converted to BBB (see Pool School). I used a bit of a different method than many on this site. At the end of last summer I let Baquacil level go to zero, shocking regularly for two weeks with monopersulfate non-chlorine shock. I then closed for the winter with only poly-quat 60 algaecide added. I opened opened and began bleach shock treatments. In less than three days I had a crystal clear pool with stable free chlorine. If you already have the stuff in the pool, chances are you won't have problems this year. Sooner or later you will (four years seems to be my non-scientific guesstimate). If everything remains OK over the summer, I would advise converting using my modified method. Otherwise, visit the forum on converting and you will get a lot of good advice.