Ph, Alk, and Calcium

I just did my once a week water tests and my alk has dropped to 4, Ph at 7.7 and my Calcium is over 600.  I just added some buffer and mixed up some Mrs. Wages with about 2 tbsp in a gallon of water.

I've never added kalk before so I want to get some opinions before I added it to the system.  I know to drip it slowly over several hours.  How much should I add and should I wait until I get the alk back up to 10 or better?

Jon - I know that this is your expertise, so I'm counting on you chiming in.

Tell us more about what you've been adding to your tank.  How did the calcium get so high?  At first blush, I'd say you've overdosed calcium some way.  This will drive down the alkalinity.  pH will trend down along with the alkalinity drop.  Where do your nitrates normally run and where are they now?

What I would suggest is to continue to add buffer until your alk gets back where you want it (2.5 - 4.5 meq/l).  Continue to monitor calcium, it will decline with time.  As the calcium declines so will the alk, just add more buffer to maintain alk at the level you want.  When the calcium gets to where you want (370 - 460 ppm), then if you desire, start using kalk.  I probably wouldn't use any kalk right now it could lead to bigger then desired pH swings.  If you do add it, go slow (maybe a pint or so tonight) and see how the tank responds (with calcium that high the kalk might drive alk even lower).  Don't get me wrong, I'm a big fan of kalkwasser.  I just don't think it should be used to raise alk/ca.  It's a maintance (ie maintaining current levels) product.

Overall, not that big of a deal Sean (so why did I write so much ).

More specific info:  If you use baking soda for alk, you'll need 13 tsp to raise 100 gallons of water from 4 dkH to 11 dkH.  I would not raise my alk by more then 0.5 meq/l per day (1.4 dKH) so do this over 5 days.

Sounds like a good plan to me...

(been thinking more about a calcium reactor?)

How long?  It all depends on how fast your tank is consuming calcium (making CaCO3).  Just go slow, as you add the buffer some of the calcium will/might precipitate.  You want to avoid this, imo.  If all that precipicated was CaCO3, then it wouldn't be a concern, but unfortunately strontium, magnesium, and others to a lesser extent, can also precipiate.  Let me revise my advice a little from above.  Don't raise your alk all the way up to 4 meq/l this week, bring it up to say 2.5 meq/l (7 dKH) and hold it there until your calcium drops down into the lower 500s or upper 400s, then move your alk up to 10 - 12 dKH.  Just hold where you are if you notice hazy water.  Did you get hazy water from the turbo calcium additions?

You could always do a water change... but I'd just add a little buffer and wait for my calcium to drop.