I’m setting up a new enclosure and was wondering about some things.

I have had a few plant display terrariums over the years and I have found that a layer of activated carbon (sometimes I’ve seen it as charcoal, but it’s the same thing) on the bottom to help keep the soil “fresh” and ward off fungi. I was contemplating adding some into my roach enclosure since it occasionally seems to become stale. Does anybody else do this? As far as I can reckon I don’t think it would cause any adverse affects.

Second point on my agenda, I have a heater rock the kind used for herps. I think it would work very well to get some added heat to my roaches. The problem I foresee is it might desiccate the enclosure or possibly over heat it since cockroach cages are more airtight than the standard herp enclosures. Has anybody used one before with roaches? While using it first I will keep a close eye on it of course but I was interested to see if anyone has had any disasters with them.

Thanks for any help in advance.

I'm familiar with the adsorbtive properties of carbon but am not sure how it would ward off fungi. I don't think carbon in the substrate could harm a cockroach.
I've had heater rocks in the past that were warm and could be great for certain roaches but I've also had rocks that nearly burn your hand. Have they become more consistent in recent years?

I have just heard that the activated charcoal helps ward off fungi but I'm not sure if it does or not, I have noticed that it does keep things fresher though. I wasn't sure if they would try eating it and once ingested it might produce gasses in the digestive system and cause some harm. It's pretty hard stuff so I doubt they could really "bite" it. My heat rock seems to be pretty consistent; I might just kind of cover it with some substrate so the roaches won't have any direct contact with it. I suppose I'll give them a try in a coule days and keep a close eye on it.