Coraline on glass but not on rock

[argileh]

Originally Posted by reef_raf

With that much rock and sand, I'm surprised you have any NO3. What do you feed? Frozen foods can add a lot of nutrients. Is the sand bed old(over 3 years)? How about the rock? Is it clean on the surface? Try using a turkey baster to clean it off and open the pores, the internal (anaerobic) surfaces are where the NO3 is broken down, make sure the water can get in there.

I basically feed formula one flakes. The sand bed (which is about 3/4") and the live rocks are nearly a year old. I set up the system last September. I am suspecting the additives I am using. Currently I am dosing Salifert's All in One and Coral Calcium. When I set up the system last year I was using C-Balance only and there was more coraline on the rock and less on the glass. When I ran out of C-balance I decided to try Salifert's additives and it might be they are the culprit. I will switch to C-balance again and see if it makes a difference. I also got my Iwasaki bulb and hope it helps too (BTW the bulb is fantastic)