xinumaster
reef addict
You know that is the reason why I use seachem matrix. I don't need to replace it. Only, the sulfur needs to be replaced when they run out of steam; which is the reason why sulfur is on the top -- it makes easy to replace it. By the way, I learned this method from new jersey reef club. Calcium media is also okay to use. It will house the bacteria and at the some time dose CA in your tank.