Hi everyone never used a forum before so if I am doing this wrong by replying to some's thread sorry, I have a 3500 litre pond with a few gold fish 2, 3-4" butterfly koi and a 1 foot gold koi which is temporary. I have owned my pond for a year next month and never had any major issues, can anyone tell me is it possible to add two filters to a pond system, my original filter has a uv, it's just a real pain to clean with been round rocks and other things so I was planning on putting one in with out a uv, just simply to make life easier for me, plus wont it make the water cleaner with double filtration?? Also can you completely empty a filter box to clean it entirely, of course not washing the media out,! Are these thing doable? Thanks for reading!