What is the proper size cartridge filter for my situation?

[mobilemike73]

I have a 10,000 gallon AG pool, along with a 2HP pump and 100# sand filter. The pump is far too powerful for this filter and my pool is cloudy because the algae is getting blown through the sand due to the powerful pump. It's been filtering for weeks and the water is still not clearing. (My water chemistry is just about perfect, and I have had FC in excess of 10ppm during this whole time).

Question 1: Can I use the sand filter as a pre-filter and connect a cartridge filter to the return side of the sand filter? This way only the smallest particles make it through to the cartridge filter, hopefully prolonging cartridge cleaning cycles.

Question 2: What is the appropriate size of cartridge filter to use for a pump this size?

Any advice appreciated.

Thanks!
Mike