Is Carbon bad or good for reef tanks

i'm pretty sure 99% of all reefers yours both with know problems

 

Loaded question. And one that will bring multiple opinions. Here is mine. Carbon does removes organic compounds. Some of which may have binded up some ofnthe trace elementa. But nkt really enough to claim that it removes them. But the reality is that there really hasn't been any solid arguments in the detrimental camp.
Long and short. Carbon is used to remove dissolved organic compounds from the water. The effect of organics simply cause the water to take on a yellowish appearance depending on tiur tank this organic mayter can consist of complex organic toxins produced by the inhabitants. Dissolved substances are not directly consumed by higher animalia and are mainly consumed by bacteria and algae.
There has been arguments that it some how effects sps but I still belive that the water clarity increases PAR burning out the corals.
Carbin as in freshies can fill up and then leach phosphates. So change it out. Other than that I have been running charcoal for... 15 years or so? No issues here.

 

I run bot also. Its on sps tank no problems. Just be careful running gfo if you drop phosphate too fast you can have problem.