I used E.S.V. B-Ionic Magnesium 1 Gal and loved it. I also bought http://www.amazon.com/gp/product/B003U4TL3U/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1 these to make dosing easier
Red Sea Prism Energizer protein skimmer hang on back-sells for 100
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