Can carbon cause RTN?

[banzai75x]

I stopped using carbon because I was doing the Kent M MG trick to get rid of bryopsis (which didn't work for me BTW.) So during this phase, I stopped using carbon.

Yesterday morning, I added carbon back to my system in a bag in my sump.

When I came home @ lunch I noticed 3 of my SPS frags RTN'ing. Half of each of the frags were bleached/white. I freaked out. I cut away as much of the dead skeleton I could preserving what appeared to still be alive.

I removed the carbon @ lunch.

Last night it looks like the RTN stopped. I still saw a little bit of tissue loss but not as much as before. This morning it still looks the same.

Tank has been pretty stable otherwise. I tested everything and they are all within normal limits.

 

[Allmost]

yes, too much carbon can drop DOC sugnificanty, which can in turn cause stress and RTN in SPS.

I would put half the GAC back in, and increase to the value that is needed within a week.

when you run carbon all the time, it keeps the DOCs low to certain levels, it never gets to climb really high to make the next exchange stressfull for corals.


the graphs here can explain things better.
DOC