SLB Splmt Replenisher 2# 24BLKBrand: All Seas Marine Features: Formula #28 Always works, and cannot be overdosed This is not a slow dissolve or time release product. It dissolves only to replace depleted elements Saltwater Use only Block box contains 24 blocks (2 lbs) model number: 024 28 Part Number: 024 28 Details: Automatically controls concentrations of 28 elements including calcium, strontium and all 15 essential trace elements. Removes heavy metals and limits ammonia and