It'll lower naturally as your corals grow.
Have you checked your mag? Personally, I think it is important, so your CA and alk aren't binding to each other and harder for your coral to use. Having low mag can swing your numbers. I agree that you don't use up mag quite as fast though, unless you have a 3' mangrove.
How are you liking your Red Sea kits? I like the titrator idea and the fact that they sell reagents separate instead of having to buy a whole new kit.
One more thing about water changes, a wise man once told me that smaller water changes are more stable for your tank than larger ones. So I will have to say the smaller ones 2x week would be better. Perhaps you should try both and see which the coral like better? HTH
Sent using Forum Runner