Ich disappearing and reappearing with a vengence is the normal life cycle of ich. To get you tank to hypo you need to change out 1/5th of the water in your tank with fresh RO water every 12 hours until the salinity reaches a level of 1.009%. This shoulf take just over 48 hrs. Ich wiil die off at this salinity level as will your LR, inverts, corals, and LS. You need to closely monitor PH. If you run hypo on your MT you need to maintain 1.009 for 3 weeks after all signs of ich have cleared. Then on the 4th week slowly raise your salinity back up to normal. Raise the salinity very slowly over a week. If you have LR you will need to remove it from your MT and keep it in a rubbermaidcontainer with water flow and heater during the treatment. When salinity is back to normal, watch the first for a week checking for spots before returning LR to tank. If you remove the fish from the MT to do hypo or copper, the fish will need to remain out of the MT for 5-6 weeks to let the ich in the MT die off naturally.
