stumped on low ca levels

[liquidfunk]

I have a tank that has been set up for about 18 months. 150 tank, 25g fuge with macro, 30g sump. I run a PM reactor, and a DIY kalk reactor that doses straight clear kalk water for top off. (total of 44 inches to clarify foggyness). My CA in my tank yesterday was 320ppm. I tested my freshly mixed SW at it was 430ppm (to test the kit, and maybe bad batch of salt). My alk is 12.5dKH, and my magnesium is 1500ppm. I have dumped about 6 oz of turbo calcium in the last week and it actually dropped my ca from 360-320.

I tested my affluent (sp?) out of the reactor, its 6.25 (with digital precalibrated unit) with a 500ppm ca level.

any idea what could be sucking up my calcium? I have alot of SPS, but they are all frags. I also have loads of macro algae, and 4 clams but I dont know what would possibly suck up that much ca. Should my reactor be dosing a higher PPM?

Thanks Randy, your the best help for this stuff!!!

(I harrassed you lots before regarding a 24dKH alk issue... about a year ago. that is since resolved with new sand.)

[Randy Holmes-Farley]

Are you adding any buffer or alkalinity supplement other than the reactors?
That could push calcium down.

You probably just need to add more calcium chloride to correct the low calcium, although that doesn't explain how it got low. This calculator will help show how much:

http://home.comcast.net/~jdieck1/chem_calc3.html

I tested my affluent (sp?) out of the reactor, its 6.25 (with digital precalibrated unit) with a 500ppm ca level.

This is a CaCO3/CO2 reactor? It ought to raise the calcium by about 20 ppm for each 1 meq/l of alkalinity (that is, that much above the tank water that enters it). What is that alkalinity value? meq/l?

[liquidfunk]

yes its the CaCO3/CO2 affluent I was refering too. Ill have to test the affluent alkalinity tonight, I havnt tested that recently.

I have been dosing "Kents liquid reactor" and some turbo calcium. I think the liquid reactor is balanced ca/alk, but isnt the turbo calcium straight calcium chloride? Is there a cheaper alternative to turbo calcium?

Any ideas what would be eatting up my calcium without lowering my alk?

I did a ca test on my freshly made SW and it was at 430ppm ca so I dont think its my salt, nor my test kit.

[liquidfunk]

Holy smokes that calulator says I need 750ml of Kents Liquid Calcium. any idea which one is the highest value?

[Randy Holmes-Farley]

The Liquid Reactor is very useful, IMO.

Any ideas what would be eatting up my calcium without lowering my alk?

The only thing that does that is supplementing alkalinity and not calcium.

Holy smokes that calulator says I need 750ml of Kents Liquid Calcium. any idea which one is the highest value?

Highest value of what? You mean cheapest?