Yeah, tell me about it!!! I had no idea why I had so many issues initially and took a sample to an lfs and they told me I had high phosphates. I had no idea what that was so I took another sample to another lfs and they said the same thing. (I am a slow learner sometimes...) After learning about phosphates and reading up on GARF, " http://www.garf.org “ I decided remote DSB (deep sand bed) was what I wanted.
I knew intrinsically that it worked well when I kept fresh water fish twenty years ago to have a deep bed of gravel and cringed at the thought of getting rid of the gravel and replacing with a sump full of Bio Balls 15 years ago when I converted to Salt fowlr setup. Now moving up to reef, It was time to get rid of the balls and go back to DSB. I didn't want it in the tank so I set it up in a large sump.
That's what I LOVE about this hobby though, always learning something! Unfortunately, I am the kind of person that USUALLY learns from my own mistakes. Sometimes I have to make the same mistake repeatedly but, I guess I will eventually learn something huh?