Raising dKh

[workman]

Looking for input on a what I beleive is an imbalance issue. I am using limewater (2tsp per gallon) to help maintain Alk and Calcium. My calcium is good stays around 390 - 400. My Mg is around 1350. However my dKh is only in the mid 7's. I have been adding baking soda in an attempt to raise the dKh (Ph is normal). All my test kits are Salifert. This is a 220 gal display.

When I have added the baking soda, I have taken about a cup of ro water and warmed it to help the soda disolve. Any chance this is impacting the process? I have been adding anywhere from 4-6 tsp of baking soda per day and am not seeing any movement.

Everything in the tank looks great. Any expereience with shelf life of test kits (this one is about 13 months old)?

Thanks, Mark

[Randy Holmes-Farley]

That seems like a fine plan. Limewater often cannot keep up in high demand systems, and they way that first shows up is alkalinity starts dropping lower than you'd like. :)

[workman]

Thanks Randy - Have you had any issues with using warm water to improve the solubility of the baking soda? What would be the recommended dKh level for Calcium at 390-410 and Mg at 1400. I have seen some slightly conflicting information.
Thanks, Mark

[Randy Holmes-Farley]

Have you had any issues with using warm water to improve the solubility of the baking soda?

No, you can use boiling water if you want. It drives off CO2 and makes it also have a pH boosting effect, like my DIY two part Recipe #1 or other two parts like B-ionic. :)

The optimal alkalinity levels are not tied to the calcium level. I recommend 7-11 dKH regardless of where you maintain calcium. :)

Some folks have misinterpreted a "balanced" calcium and alkalinity level to mean that is the target, but that is not true. It simply means seawater plus or minus an amount of calcium and alkalinity in the ratio that corals would use it. But just because calcium is, say, 500 ppm, certainly does not mean the optimal alkalinity would be the balanced 18 dKH.

[workman]

Thanks Randy. Where do I find your two part recipe?

[Randy Holmes-Farley]

Here:

An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System
http://reefkeeping.com/issues/2006-02/rhf/index.php

[workman]

Thanks Randy - Much appreciated!

[Randy Holmes-Farley]

:thumbsup:

Happy Reefing. :)