So I recently started getting back into the hobby after a move and happened across a fish I had to have. I have unfortunately not had the time nor money to pick up a tank for quarantine. As I'm sure you can guess by now when I got the fish in my tank and under further inspection it is in fact sick. I have the meds already no problem there. My question is all the meds say use a carbon filter after the final dose and water change, I do not have a carbon filter and will not have the money to get one. How big of an issue is that?