My line runs about 65 feet out and sits about 2 feet off the bottom in about 15 feet of water. I have the charcoal filter, sediment filter, and UV chamber and that brings it to drinking quality water. I replace the filters and the UV light once a year, every spring.
This is a link to the system I have:
https://www.freshwatersystems.com/pr...SABEgLT5PD_BwE
The bigger filters cost a lot more so I left the old small filter in place before the new system when I installed it. The small sediment filters are about $5 at Lowes and I change them every couple of weeks. I figured if they caught 80% of what came in it would make the big filters last all season. So far so good. It has worked well for about 5 years.