I'm working on getting a larger tank, but came accross someone selling a used Eheim 2217 for $100. (Super deal here in Canada) I've been researching this filter and it's aparently really good, but I have some confusion about the filter media. I noticed it has 2 baskets inside. It uses those ammonia tube things (I'm very technical can't you tell?) and the person said something about a foam peice and cotton peice. I'm assuming the cotton is the loose stuff you buy in bulk, but what about this foam peice? First of all is it really necessary with the cotton? Also what about charcoal? Can it be used in this filter? I've got a bunch of different info from sites on this filter, so I was wondering if someone had one and if they could clear up some confusion...
Thanks!



