I was in the same situation last year. I had a cartridge filter ... I constantly had to clean it to keep the flow up. I would need to change it weekly if not sooner. By the end of the season both cartridges were trashed and I had to buy 2 new ones each year. I was spendign 100 dollars a season on filter, constant maintenance and always fighting algea.
Pretty much my story, too. I was also cleaning daily. I was going through about three cartridges a season. I also decided to get a sand filter.

Except ... I converted to chlorine, first. I still haven't bought that sand filter. I'm still on my first cartridge filter this season. It NEVER goes above 10 psi. I do clean it once a week - I'm getting a lot of dirt blown in from a three acre lot behind that is being developed. My pool is always crystal clear.

Carl is right, bacquacil too easily clogs up the filter, making it ineffective.