One of the bags of activated carbon split in my external filter and bits of charcoal got pumped all over my tank (right after I'd cleaned it as well!) I've siphoned up as much as I can but there's still the odd bit here and there. I can't imagine the bits being large enough to cause impaction or anything like that, but is there any chance it could harm them in any other way if they swallow any? I'm probably being paranoid but it's better to be safe than sorry.

I've removed all of the carbon from my filter now as well. I only had it in there because it came with the filter so I thought I might as well use it as extra surface area for bacteria to grow on. Stupid porous bags.