Mixing up an A/B solution

[ReefDream]

I would like to switch from kalkwasser to a homemade A+B solution to see if I experience better growth in my coral. Of course, I would also do regular water changes to reduce the build up of sodium chloride.

Assume that I am using calcium chloride in the dehydrated form as in well-kept DampRid (never exposed to outside air for any length of time) and intend to use calcium carbonate (Arm and Hammer washing soda) what ratio on a per-weight basis would make a balanced pair of solutions given equal parts water in both the A and B solutions? Is there a way with a pH probe to verify my solutions are balanced; that is, could I mix them and check that the pH is near neutral or check the alkalinity is close to zero? If I were to mix them, how could I make sure that both have fully reacted? Heat the mix?

[Randy Holmes-Farley]

and intend to use calcium carbonate (Arm and Hammer washing soda)

That would be sodium carbonate. Going forward, my suggestion is to use baking soda. You can bake it or not as you see fit based on pH needs. The advantage of baking soda is that it must be food grade, while baking soda need not be.

I give the full recipe for a DIY two part in this article:

A Homemade Two-Part Calcium and Alkalinity Additive System
http://www.advancedaquarist.com/issu...l2004/chem.htm

I do not know if Damp Rid is suitable pure, but if you use it, use 20% less than my recipe calls for Dowflake.

I do not think there is an easy way to verify that they are balanced. The best you can do is mix them,let them settle to total clarity, then measure alkalinity in the leftover. I personally wouldn't do that.

[RustySnail]

Roger-

What is your tank's Ca/Alk with limewater? You might consider supplementing the limewater with A/B to boost the Ca/Alk level if your corals are out-competing the limewater top-off. Since raising my Alk levels up into the 9-10 dKH range I have noticed rapid growth of all the corals in my tank (both LPS and SPS). For example my frogspawn now has 3-5 heads on each single branch where there was only one head before (in about 2 months); and growth is visible on the SPS corals from one week to the next.

If you use Washing Soda; be sure it does not have scent or soap smell when mixed. I noticed a soapy smell after mixing Arm&Hammer washing soda so I ended up dumping it and switching over to baked Baking Soda. I had already put a fair-bit of washing soda in for alk uptake and it did not cause any problems before noticing the soap/scent, luckily it did not cause any problems (besides fueling the bit of HA that I cant get rid of).

[ReefDream]

Randy, you were too kind in replying. I must apologize for not doing a proper internet search before asking. Here you write a bit cool article all about it and get the same old questions--you'd think some people can't read.

RusySnail, my calcium is fine. My alkalinity, on the other hand, has gotten totally out of whack. All the coral are okay, except growth is terribly slow and I am losing some color here and there. Eventually it bothered me enough to do a few tests--the first in two years--of my calcium and alkalinity using some new Salifert kits. My calcium is 420, but my alkalinity is 4.0 dKh (yikes!) That would explain the sluggish growth.

I would never have expected me to be at this point because I dose 3 gallons of full-strength kalk a day into my 120 gallon tank. I was so confident that this would be plenty that I sold my calcium reactor last year! And today I realize that even 3 gallons a day isn't enough and I just can't evaporate any more water since I have fans all over the tank. I have to change my strategy.

[RustySnail]

Yep... It's simply amazing the amount of calcium the corals will utilize in a healthy tank. Your calcium level stabilized at 320 because the corals could not build skeleton with Alkalinity that low (the limiting factor is carbonate not calcium as Randy has nicely explained in this article). So once you get Alk levels back up, watch out because the Ca level will also start dropping like a rock

I was adding 100ml of each the A/B per day to my tank in addition to 2gals of limewater. I just recently switched to Ca reactor (same as you it has been sitting in storage for 3 years). My Alk is now fairly stable at 10dKH; I only occasionally have to add some A/B to bump it back up to 10.

Use Jdieck's Calculator to determine the amount of various additives for boosting or maintaining levels.