Uh, no. I don't know what all brands say on this, but I used to use Seachem 2-parts (Reef Builder for alk and Reef Calcium), and the instructions said to wait at least a half hour between the two. I myself found it simpler to get in the habit of adding one in the morning and one at night, but YMMV of course.

Since the Seachem stuff is powder I would predissolve the stuff, and I found if I had just the slightest amount of residue on my stir stick from the previous mix, the reaction was so exothermic that the water would literally be boiling hot for an instant (if I had my hand under just the right spot). Then there would be an instant coating of calcium carbonate where the two additives had mixed.

Kalk/ replacing evaporated water
 

I was contemplating dosing my tank after I get my new skimmer up and running. I've read the two best ways are to use kalk or a 2 part system. B-ionic and C- balance recommended. When you guys say to replace evaporated water with Kalk could you elaborate. I have two 27 gal tanks. I hope to interconnect the 2 in the future. The reason I'm leaning on the 2 part system is the reading I did says that with smaller tanks it is affordable. Its seems to me it would be easier than rigging up a system to drip the kalk. If adding the Kalk is not to complicated I would go with that, because it seems cheaper. Your views and recommendations would be appreciated. When I say dose I mean I want to start keeping the calcium level where they should be. I haven't ever done this yet. My tank profile is not up to date I haven't been able to figure out the new stuff on the board. Not to bright when it comes to finding my way around the board.
Thanx in advance George M.

My tanks
 

ok I've put my specs for the 1 tank in the Tank Specs forum. I couldn't find room for the 2nd tank. It has about 10 lbs of live rock and a 3in. sand bed. bugs galore and a few crabs and snails. some algae is growing halimeda. The goal is to get the skimmer hooked up. Its a prism. Then I'd like to interconnect the two with a pump and some tubing still looking for some ideas on that. I'm rambling. i would like to get my calcium levels up to norm. I know water changes cannot replace the calcium. So any pointers appreciated. And pointers on how to hook the two tanks together and so on. Thanx in advance George.

Kalk can be added with just a jug or something more complicated. Just use a large jug type container. Throw in a spoon of kalk, fill with ro water, mix it up for awile and then let it settle, until the residue settles on the bottom.

You can drill a hole in it, about an inch up from the bottom, { so the residue does not drip}, and silicon an airline valve in. Just sit the jug over your tank or sump and turn the valve on to get a decent drip. Best to add kalk at night, when ph is lower. Kalk should be added slowly, whatever method is used, as it has a ph of 12.

I have dripped like this for many years, from 50g tanks to my current 225. It just replaces the evaporated water.

Of course there are other ways, like float switches and dosing pumps and kalk reactors and even garbage cans full of kalk.

By the way, kalk is an excellent way to maintain levels, but its hard to raise them, unless there is a large amount of evaporation. Best to use something like Kent Turbo calcium, to raise it up first, if its low. Or if both calcium and alk are low, it can be raised by using equal parts of a 2-part.

When dripping Kalk, I know you should not use the precipitate at the bottom of the mixture, but I also heard that you should not use the layer of crusty stuff that forms at the top? Is this true? If it is, how do you avoid the stuff at the top if without transfering containers?

I would not be to worried about all that. Over the last 14yrs. I have added it all. Never hurt a thing.

I have never worried about the top crust forming. The sediment in the bottom is best not to add. There are those, including myself, that drip the kalk still in its milky state.

One problem with that or using the sediment, is if non pure water is used in the mix, that kalks ability to precipate out phosphate from the water, builds up a phosphate accumulation in the sediment.

For newer users, I suggest either the valve be high enough, so as not to dose the sediment or after mixing, just dump the clear liquid in your doser.

It should be know though that kalk reactors continually mix the kalk up and dose as such.

While at the LFS yesterday I met two of the reps from Kent. I asked them about Calcium levels and they both said Kalk is the unquestionably best product for raising and maintaining Calcium. They said the form or calcium in the two part lowers the pH and thus depletes the alk, this is why you have to add the second part, to restore what was already there. They both agree that Kalk is much better.

They also said SeaChem Reef complete and Reef Calcium is a nice treat for coraline algae, Calcium Gluconate will speed up the metabolism of corals including coraline algae but they can get "tired of it" too much of a good thing I guess. They said to use it once in a while and everything should be great.

I have yet to see anyone successfully raise calcium and/or alk by dosing kalk. Based on opinions of chemists (Randy Holmes-Farley, Craig Bingman) rather than sales monkeys, I would say that info is not correct. I have also tried to raise levels with kalk when I first started in the hobby, and I was not successful. As an aside, I am fairly certain I have seen this same info on Kent's website at some time. I'll take a look.

Agreed. I just mix up the jug and hook it to the float valve. I don't worry about what part goes in and I've not had any trouble with it.

On that last point ..... just curious, do you find that kalk gums up your float valve eventually. If it does, how often do you find this, and can the clog be cleared by soaking in vinegar?