Is activated carbon safe to drink?

I have a Drinkwell 360 and I usually use the regular filters that are designed for it. Those contain the activated carbon too. I found a place that sells a reusable filter that only requires that you put the activated carbon in yourself (from pet store) and change it like every 2 weeks (I change every week though). Anyway since changing to this new method I have been having more carbon residue in the reservoir. Is it ok for my cats to drink? I have been looking online and cannot find a site that will tell me.

Thank you.

Activated charcoal is used medically to absorb certain poisons.

A quick Google for "Is it safe to ingest activated carbon" had numerous hits. First site had this:

"actually so safe that doctors sometimes give it to people who have swallowed poisons. but it doesn't work on every poison. do not inhale it. ."

It seems that whatever tiny amount might be in your cats drinking water is not going to be a problem.

Thank you. I think next time I clean the fountain I will start soaking the carbon pellets for a few minutes. That may help.

Perfectly safe, however, it says on the fine-print of the replacement filter box that you are supposed to run new filters under cold water for a minute to wash off any carbon dust on the outside of the package before putting it in the fountain.

It can make the water taste weird.