Stupid question alert: Ca Reactors vs. Kalk Reactors

[bureau13]

OK, this is probably a really dumb question. I've seen Kalk Reactors, and I've seen Ca Reactors, and it seems like they are intended to do much the same thing, in slightly different ways. The Kalk route seems nicer to your pH, a bit simpler and possibly safer (I keep reading about people going away and returning to find their CO2 went haywire and killed their tank...although someone was posting something about dangers of Kalkwasser too so I have no idea) but there seem to be more Ca Reactors than the other...so what's the advantage there?

I was also puzzled the other day to see someone with a large tank setup that had both types of reactor present and operating. Why would you want or need both?

jds

[Casino]

Calcium reactors do just that, add calcium. Kalk reactors add both calcium and alk. Calcium reactors tend to drive the PH down so most use the kalk reactor as well since this helps bring the PH up. If you have a big tank with calcium demanding SPS's, then a calcium reactor will be beneficial for you, and if your PH is low, hook up a kal reactor to help this out. If not, you can just get a kalk reactor to maintain your levels where you want them to be. Beware kalk need to be dripped slowly since the PH is over 12.

[Bax]

How big is your tank, samll tanks dose Kalk with out a reactor, say up to a 46 ish gal tank. Over this to like 90 even 125, it depends upon your coral population and Ca demand, but usually a Kalk reactor is in order with a moderate coral load. But big tanks need both as CASINO said.

[Gary Majchrzak]

Originally posted by bureau13
OK, this is probably a really dumb question. I've seen Kalk Reactors, and I've seen Ca Reactors, and it seems like they are intended to do much the same thing, in slightly different ways. The Kalk route seems nicer to your pH, a bit simpler and possibly safer (I keep reading about people going away and returning to find their CO2 went haywire and killed their tank...although someone was posting something about dangers of Kalkwasser too so I have no idea) but there seem to be more Ca Reactors than the other...so what's the advantage there?

I was also puzzled the other day to see someone with a large tank setup that had both types of reactor present and operating. Why would you want or need both?

jds
Not a stupid question!
Limewater is used in conjunction with a Ca reactor (usually) to bring up a depressed pH.
Ca reactors deliver Sr and Mg as well as provide alkalinity and Ca.
Some good reading on the subject in this link:

http://www.advancedaquarist.com/issues/feb2003/chem.htm

[bureau13]

Thanks for that link, it was very informative. I guess you would need both limewater and a Ca reactor if your Ca demand was greater than what could safely be provided via topoff water...that makes sense.

To answer the other questions, my current tank is a 55G to which I add the B-Ionic 2-part (original) supplements. I plan on upsizing to something between 150G and 210G in the next few months, so some of these questions I've been having are simply my attempts to learn enough to plan out a successful larger tank.

jds