So last night I was looking for my pleco in my new 29g tank. I couldn't find him, so I started to worry, for some reason I had the crazy though that he was inside of my filter (The area where you put the media) and sure enough he was right there sucking on the cartridge. First of all, how on earth could he have climbed up and out of the water just to hide in the filter and secondly is he going to be ok? He seemed fine, but I didn't know if the carbon had an effect on him. I will try to upload a picture of where he was. (Just to get an idea of where he was, I have the Tetra 2-10g 2 stage filtration filter.)