As far as recharging carbon, I don't think that there is an effective way to do that simply because of the temperature that is required. As far as floating it in your tank, I think that you'll get a much better result in terms of effeciency by placing the bag in a place where water flows through it, and not around it. Try and place it in the wetdry where water has to flow between baffles, or between chambers. Just leave it in there all the time. Use two bags, side by side, or one above the other, and just swap out one bag every week, and alternate them. If you are using the filter media bags, just use two of them, and put the same amount you would use in just the one, just split it between the two bags. I think that should work more effectively than switching out the one big bag every other week. You're still leaving the bags in there for two weeks, but you're getting a fresh bag in every week. Get the big canister of Black Diamond carbon (online for around 15 bucks) and that should last you for quite some time.
