Hi all, I would like to buy one of those stuff before adding any coral, but my question which size I need if my tank size 200 gallon+ 50 gallon for sump - the rock and other pumb skimmer wich will reduce the volume around 30 to 40 gallon, please advise me and how mach of media I should use 200ml or 400ml, otherwise I can make my own DIY, but I need to know the quantity of NPX bag, pleas help
