Iv had this tank running for more than 3 months. I have couple of corals and 5 fish its a 37 gallons display with an 18 gallon sump. I had previously an issue with i started my nutrients according to my hanna nitrate and phosphate were 0. So i i started dosing. And now my phosphate without any dosing is 0.04 and nitrate is 6. But i noticed i have that slob with bubbles in on some of my corals. How do i treat.

