I was curious to find out how many people use carbon? how often - 24/7 or monthly or what? and how do you get the water through it? Reactor, canister filter, hang on filter or just throwing a few bags in the sump?
I think as long as it is in a closed container so that it doesnt start absorbing things from its surroundings that it should be fine. Carbon is basicly full of microscopic holes and once the holes are filled with crap the carbon is exhausted. so if you store it in a sealed bucket nothing should be able to get to it.
I run it 24/7 in an MRC Fluidized Media Chamber. Change it out monthly. Only use a couple of cups at a time. Polishes the water great. ESV here. Seems to have the least amount of dust and the granule size seems just right.
I used to run it in a media bag in my sump, passively. Nowhere near as effective as in a chamber, actively.
You can't pack carbon tightly without crushing it. Just run smaller amount of water thru the reactor and you'll be fine, you don't want the carbon to tumble around.