Hi, I am reviewing the H&S Sulphur/Nitrate Filter which i have acquired about 1 month ago. Due to the messy sump conditions and decision to do away the natural deep sand bed and also to contain everything possible within the sump, i decided on the Sulphur/Nitrate Filter after much deliberation. Filtration Method This filtration method employed a containment with a circulating internal pump which also act as a feed pump to draw the sump water into the unit, this keep circulation in mo