I’ve been using the coral pro black bucket for 3 years. The water clarity is so clear and clean on my 90g reef. I setup 180g fish only and used the Instant Ocean salt. My curiosity is... Why do I see floating grain like substance? The water clarity is clean but not as clear as my 90g. Is it because it’s Instant Ocean? First time I’m using Instant Ocean since I didn’t want to spend too much dough on a fish only setup.