Hellow guys this is my first time posting in this forum so I would like your opinion about a particular subject. I wanted to know if a fuge can become a watse basket. I have had my tank set up 3yrs and some change. I have a 150 with a 60 gal sump. this is a description of my sump if you were looking at it head on. On my right side is my fuge which is fed from my tank. In the middle are my returns and calcium reactor and on my left side is my skimmer. In my fuge I have chaeto, sand some grape caulepra. I have no clean up crew in there and my sand bed is about 3" deep. I wanted to know if I never clean my fuge can it become a source for nutrients. Also I want to know if I could start my fuge over from scratch? If so changing out my sand in the fuge would it cause anything in my tank to spike? If I had to do it all over again my sump would have my fuge in the middle and the returns to the right.