[christyf5]

FWIW, I have a batch of carbon that is likely from prior to 2010 and well before the recall dates (I think I purchased it in 2010 but it sat in the store for awhile). I started using it late 2010 early 2011. During the past year and a bit of using it my tank has gone downhill. Lots of cyano algae, decline in coral coloration and some receeding and two corals had algae start to grow on their tips, one so much so that I ended up fragging it and disposing of the majority of it. I had no idea what was going on but I because very busy and didn't really have much time for the tank other than basic maintenance so I figured I just needed to put more time into it. After this kent issue came to light, I didn't really think my kent carbon was a problem but decided to switch to ROX for a lark (everyone raves about it). Within 2 weeks my corals were coloring up, those SPS with the algae growing tips were clipped and healed up nicely (previously they would just regrow the algae) and all of my cyano is gone. While I don't know if ROX is the answer I do know that Kent was certainly not. I still have about 2/3 of a 5 gallon pail just sitting here. I'm not sure if I will use it intermittently or just dispose of it altogether.