Ca, Alk, and Mg

[reefkeeper]

As many of you know, I am new to the hobby (and am loving it).  I have a 120 reef, 55 fug, 5 fish, 100+ lbs of LR, and a few frags that a couple of guys gave me. 

What are the proper levels for Ca, Alk, and Mg and how do you maintain these levels?  My ph stays a pretty constant 8.3, although it seems to be creeping up lately.  Could be my probe needs recalibrated.  It's been about 2 months since I calibrated it.   Thanks -Jeff

[lazylivin]

If you have had your windows open that is probrably why it has been creeping up on you.

[lazylivin]

My parameters I shoot for are as follows:
Calcium 425PPM
Magnesium 1350PPM
Alkalinity 9.5dkh

Here is a good range to stay between. You would want to pick a number in this range and do your best to keep it constant. Most critical is Alk becasue of the affect on PH.
Calcium 400-450
Mag 1285-1450
Alk 8-10dkh

[reefkeeper]

Thanks Lazlivin.  So, what technique or device, etc. does everyone use to keep the Ca, Alk, and Mg within parameters?

[CoralBeauties]

It really depends on what you are keeping in the tank and how much of it.  With just fish it really wouldnt require any additions. Routine water changes will keep most of the parameters good.  If you start adding corals and inverts that consume ca you might need to start a routine of adding a 2 part solution or using  kalk water as top off water.

[lazylivin]

As jjoos99 stated just water changes with a good reef salt works well with lightly stocked reef tanks in addtion to possible needing to add a PH buffer. As you add more corals or begin getting a lot of coraline algae a regular dosing method may need to be put in place. The most inexpensive is adding saturated limewater. You can get a Kent doser for about 30$-40$

Basically you just add RO/DI water and Kalkwasser powder to it and let it drip in the aquarium over a couple of days to week depending on the depletion level. In addtion to being the least expensive option it can also help with the daily top off chore. There other methods for dosing a reef aquarium that require less maintenace but are much more expensive and for moderate to heavily stocked reef tanks or those that just like to have complete automation.
Keep up with the routine testing of your chemicals and let us know if you are having trouble keeping them stable and we can give some recomendations based on the depletion rate.

So, what technique or device, etc. does everyone use to keep the Ca, Alk, and Mg within parameters?

I have a moderatly stocked SPS reef tank and dose twice a day. It is complety automated for CA and ALK using two perastolic dosing pumps and bulk chemicals. The alk doser connects to a timer that turns it on for 35 minutes twice a day. For peace of mind I have the timer connected to a ReefKeeper 2 that will shut off the the timer if PH goes over 8.3. The Calcium dosing pump is connected to a timer as well and runs twice a day for 35 minutes. No safe guard on that one which is probably not needed becasue of precipitation. I add Magnesium twice a week manually.