Possible precip...

[Footbag]

I've been trying to raise my Ca and ALK from my current Ca 380, dKH 7.0 to no avail. I have been dripping kalk(3Tsp/g) w/vinegar and also adding lots of C-balance. My levels aren't increasing and It seems like I cannot keep up with my SPS coral intake. I am wondering if it is more likely that I am losing it to precip. My PH goes above 8.45 every so often and I am now noticing calcium deposits on pumps, PO4 reactor and in the return line.
Am I precipitating all of my additions? What could cause this and how can it be corrected? Should I discontinue my Kalk drip?

Thanks again,
Adam

[Randy Holmes-Farley]

Do you see a lot of precipitation on your heaters and pumps?

The higher the pH goes, the more likely is abiotic precipitation, but a pH of 8.45 is not really a problem. Above pH 8.5 becomes more and more of a concern.

Low magneisum can also lead to precipitation, but it is quite likely that you simply are not keeping up with the SPS demand if they are growing fast. That is why many SPS folks resort to CaCO3/CO2 reactors.

How much C-balance? What happens to alkalinity if you double the amount of daily C-balance for a few days?

[Footbag]

Yesterday I broke down my return line to clean a SCWD and I found a lot of precipitation. Last week I had a pump seize. I am also finding a lot on the baffles of my sump. My system is 22g overall, but the SPS are growing in the 7g display. I am thinking that it is unlikely that 7g worth of SPS could consume 22g worth of Ca and ALK and outpace the addition of Kalk and C-balance. I did a 25%WC and will do another in a few days.

What would I be able to do to prevent this precip? I am getting a Ca reactor as a gift for Christmas. Will this prevent it?

[Randy Holmes-Farley]

I'd check the magnesium level, try to lower the pH a bit more (more vinegar,or use a two part additive that does not raise pH (like B-ionic bicarbonate or my DIY made from baking soda) or possibly add more vinegar. A CaCO3/CO2 reactor will drive down pH and reduce the precipitation, yes. :)

Here's the DIY two part recipe:
A Homemade Two-Part Calcium and Alkalinity Additive System
http://www.advancedaquarist.com/issues/april2004/chem.htm

[Footbag]

Thanks for the quick reply and the recipie...
Would you recomend that i discontinue the Kalk drip or use a weaker solution given the precip. I'm thinking that it would lower my PH enough that I could get away with using a two-part until the reactor comes.

Mag test is on its way.

[Randy Holmes-Farley]

I'd just try a little less lime in the water and see what that does for the pH.