New pool owner having problems getting the pool to clear up. I've been working with pool store and pool is still not clearing up, still very green. There is some debris on the bottom mostly on either side of the skimmer - at least when I brush it when I see the most debris. Recently bought brush to scrub pool (above ground 14000 gallons - 24 round). Think I might need to vacuum it but sure what to buy without spending too much, but want to get something i won't regret later. I am also second guessing if my sand filter it working but am unsure how to verify it is working correctly. The last couple tests from pool store only indicated it needed more shock and Cyanuric acid. Pool store recommend to start using "no mor problems" algaecide, however there hasn't been much change after 2 treatments. Any suggestions would be greatly appreciated. Thanks in advance.