OK... my 2 cents worth...
Your
pH seems low. It should be stable at 8.2 to 8.3. I would recommend that you test the Alkalinity of the water. This should be in the range of 7 to 10 dKH, which I think equates to 2.5 to 3.5 meq/L. I suspect that you will find that in is lower than 7 dKH. Fixing this should bring your
pH into the right range.
Next, I would also test Calcium. This should be between 350 to 450
ppm. The reason I suggest testing both is that they are related to eachother. Below is a very good article. I recommend reading it.
http://www.reefkeeping.com/issues/2005-11/rhf/index.php
Be warned, the article is fairly technical, so it will probably give you far more info than you need for basic water quality. Thats all I have for now.
