It takes awhile for a filter to clear a pool and like I mentioned before your pump is awful big and may just be forcing debris, including dead algae, right through the sand instead of filtering it out. You might try adding a little DE to your filter. Sometimes that helps. Run your pump 24/7 while you are working to clear it.

http://www.poolforum.com/pf2/showthr...to-sand-filter

As far as the bugs, I have no suggestions. Sorry.