Alkalinity and calcium problem

[joelsaxton]

I ran out of CO2 and I didn't have time get the tank refilled for a week, so to make up the difference, I added baking soda and calcium chloride. I also have a nilsen reactor for topoff. The pH looks fine (8.3) but the alkalinity is now sky high (over the limit on the Salifert test and 6-7 meq/L on the FasTest) and the tank water is cloudy and the Ca level has plummeted to 150 ppm. The corals look very stressed so I wanted to know how I can raise the ca and lower the alk simultaneously. I used a lot of CaCl so I am surprised it is so low. The Ca reactor is back in operation, but has not returned things to normal yet.

I am adding small amounts diluted HCl in hopes of eliminating some of the excess Alk. Mg levels are at 1300-1350.

[bertoni]

The HCl will reduce alkalinity, but water changes are safer. I'd probably do some if I were in that situation.

You could try adding calcium chloride, which might precipitate out some of the alkalinity. If not, then the alkalinity should drop on its own.

[joelsaxton]

I disabled the ca reactor to keep alk low and will just add water instead of topping off with nilsen. I added some kent liquid calcium and will add more later tonight. I also am adding a little diluted HCl, but I might stop doing that and just let it settle on its own.

[bertoni]

Sounds like a good plan to me. Good luck!

[Randy Holmes-Farley]

Watch the pH with adding HCl. Very low pH is likely a bigger problem than high alkalinity. If the alkalinity is 6 meq/L or less, I'd just let it drop on its own. :)