Single or dual Calcium Reactor help please.

[StupidsReef]

Ok I now have the dough to buy a Calcium Reactor but I'm stuck at a crossroad. Single chamber or Dual?? Everything I've read in books, and on RC's On-line mag suggest going Dual, but then everyone I talk to says either I dunno or single. So what are the pro's to each or are they different really is the question??

I will also be buying a Nelson/KalK reactor in which I will fill with pickling lime and it will run at night when PH levels tend to drop. But I wanted to know if anyone here had their suggestion on which one to use, a Single or dual chamber and why you suggest it??


Thanks Stupid.

[SaltTinker]

I have two single-chamber calcium reactors.

A friend tried to add a second chamber to his. He had problems trying to dial it in and kept getting co2 build up in the second chamber and would stop flowing. He took it off.

The extra chamber is supposed to utilize more of the co2 to dissolve media in the second chamber. CO2 is pretty cheap and my unit produces enough calcium as another unit is not necessary.

SaltTinker

[SDguy]

If you have the room, get a dual chamber. I have a single chamber...it depresses my tank pH some....so I have to drip kalk. I simply didn't have the room for a dual chamber unit.

[ReefDent]

I've had both a single and dual chamber Calcium reactor as well as a kalk reactor. The dual chamber didn't really seem to do much for my pH (pH stayed around 8.0, which was about the same as when switching to the single). Adding a kalk reactor, however, really did. I can pretty easily keep the pH up around 8.2.

I'd suggest a single chamber reactor and then a kalk reactor, if you have the room, over a dual-stage reactor (like you are planning). Also, the reverse flow of the GEO reactors sucks up and uses the CO2 trapped at the top (there really isn't any) and is much more efficient with CO2 use.

Also, consider getting a controller to help minimize the chance of over-doing one or the other (or both!)

James

[SDguy]

<a href=showthread.php?s=&postid=9800512#post9800512 target=_blank>Originally posted</a> by ReefDent
I've had both a single and dual chamber Calcium reactor as well as a kalk reactor. The dual chamber didn't really seem to do much for my pH (pH stayed around 8.0, which was about the same as when switching to the single).

Just curious (not disagreeing since I only have experience with a single chamber unit) why you think you didn't see a difference? I mean, there has to be some difference since one has an effluent pH below 6.5 and the other a pH above 7.5.

[ReefDent]

The difference in the two chambers was minimal. I think I ran the dual stage at about 6.8 (from the first chamber). The effluent (after the second chamber) was not above 7.0, let alone 7.5.

I think that if a media dissolves at a pH of 6.7, for example, not much can happen if the pH is not at (or very near) 6.7. This is why our live rock (and dead coral skeletons) does not dissolve. Increasing the pH, it seems to me, would mean that less calcium carbonate (and other goodies) would remain in solution. The output of the first chamber is whatever you set it at. The media would raise it some, just not a lot, I think.

If you were to fill the second chamber with a media that dissolved at a higher pH, say 7.0, then maybe something would happen.

It's been a few years since physical/ analytical chemistry, so maybe my reasoning is flawed...

James

[jamesdawson]

FWIW,

I use an Austin Oceans (lincense-built Barr Aquatics design) MoCalc 300.

http://reefcentral.com/forums/showthread.php?s=&threadid=998293&perpage=25&pagenumber=2

I run ARM fine media and only a PH of 6.9-7.0 in the first chamber.
The second chamber ups the PH of the effluent up to 7.5ish. In any case, my tank PH stays at 8.3 during the day as a result (8.1ish at night).

James

[ReefDent]

I wish it would have been that way with my old MRC!!! Maybe I was running the ARM at too low a pH?

James