simply following the instructions on the bottle, you can calculate how much copper it should take to get to therapeutic levels. Take that total number and divide it by, say..... 4. Over 4 days dose that amount of copper into the tank testing an hour after each dose to be sure you haven't over-shot your goal. Once you reach 2ppm, the levels will stay there unless you keep something in the tank that will absorb copper (live rock, sand, ect). Water changes will also lower the amount of copper in the QT, but as long as you add copper to the new water before adding it to the QT, you will be able to maintain your 2ppm of copper.