Hello, I have a really dirty inground fiberglass pool, the color of the water is dark green almost black, I attempted to clean the deep end but it seems to have a large amount of debris and leaves. What's the best way to get it cleaned? is there an external vacuum that I can purchase/rent to remove all the debris? I had pool companies suggest draining the pool and starting over with fresh water? is that process safe, any good/bad experiences? any suggestions would be appreciated?

Thanks,
Aboabdo