Arefugium is connected directly with a show tank and is intended to be used as an additional "living filter" by the use of macroalgae. #ed_op#BR#ed_cl#A quarenteen or sick tank is a tank separate from your show tank that you can quarenteen sick or new fish and medicate them if needed. This way you are only medicating the quarenteen tank with the sick fish instead of your whole show tank.#ed_op#DIV#ed_cl##ed_op#/DIV#ed_cl#