Calcium Reactor vs. Kalk reactor

[Chris]

Looking to find out whats the difference, whats the benefits of one over the other.... good idea to use them both together?

[CalmSeasQuest]

I'm in the process of installing a calcium reactor (GEO 612), so I've been doing much of the same research...

Both Kalkwasser and Calcium Reactors...

• Are used to maintain Alkalinity and Calcium levels.
• Produce balanced amounts of Alk and Ca.
• Neither are intended for increasing Alk or Ca. (increase using individual 2-part)
• Are commonly used in tandem, with the Kalk dripped overnight to help support pH.

Kalkwasser (Calcium Hydroxide or "lime water")

• Kalk dosing is limited by evaporation and the resulting pH increase. It generally cannot support high demand tanks on it's own.
• Kalk will increase pH significantly and must be dripped slowly.
• It's reported that Kalk provides the additional benefit of precipitating Phosphates.

A Calcium reactor...

• Can generate much more Ca and Alk than Kalk.
• Will have a lowering effect on pH.
• Will also dissolve some trace elements that exist in the media (and can contribute undesirable elements such as phosphates.)
• Dolomite can be added to provide supplemental Mg, but it dissolves at lower than ideal pH levels and can complicate the operation of the reactor.

Based on my research, I've decided to continue dosing Kalk in my ATO in addition to the CaRx.

[Chris]

Man thanks for the info CSQ, since Kalk is often ran through top off like you mentioned doing..... since I usually go through 2-4g per day (depending on running the air and temps in/out of house) for top off I am guessing this may not be a good idea for my tank since it fluctuates quite a bit

[MizTanks]

Once again awesome info CSQ 2 questions for you. First what is CaRx? 2nd am I doing right by my tank dosing 2 part?

[CalmSeasQuest]

Originally Posted by chort55

Man thanks for the info CSQ, since Kalk is often ran through top off like you mentioned doing..... since I usually go through 2-4g per day (depending on running the air and temps in/out of house) for top off I am guessing this may not be a good idea for my tank since it fluctuates quite a bit

With daily evaporation varying by 100%, using Kalk in your ATO might be a challenge. It works for me as my tanks are LED lit and I keep my home at a steady 72 degrees resulting very stable daily evaporation. I wouldn't give up yet though - You have quite a few options...

It largely depends on you CA/ALK uptake and existing pH levels and swings. Lots of daily evaporation is a good thing as it enables to you to max-out the use of Kalk. The problem is the variability. Again, depending on your uptake, 2 gallons difference a day might lead to unacceptable ALK swings. As your demand for CA/ALK grows (SPS, LPS, clams, Coralline...) the demand for CA and ALK will quickly exceed what can be provided by Kalk alone. It often ends up being just part of an overall solution.

There are other, very simply ways to dose Kalk other than including it in all of your ATO. It doesn't need to be fancy, saturated Kalkwasser can sit in a still, covered container and be dosed separate from your ATO. Kalk Stirrers (also called Nielsen reactors) can be used with a small powerhead or dosing pump and a controller or even a simply timer. The Tunze Kalk dispenser is another simple device that works very well. For smaller tanks, the Kent doser is a great IV- style drip system that I used successfully for years.

Kalk also provides you the ability to add vinegar, thereby increasing the amount of CA in the Kalk solution and providing a carbon source to the feed your bacteria population (same as in Vodka, sugar, Vit C dosing or Bio-Pellets.)

I think Kalk is a great way to supplement CA and Alk in most every instance and can be done in a variety of ways. How you do it, depends largely on your tank specifics.

Originally Posted by MizTanks

Once again awesome info CSQ 2 questions for you. First what is CaRx? 2nd am I doing right by my tank dosing 2 part?

CaRx = Calcium Reactor

2-part works very well, especially in smaller tanks. I've used 2-part in concert with Kalk for many years, in fact - I'm just now making the move to a CaRx largely due to the amount of 2-part my tanks are requiring.

The key to all forms of CA/ALk supplementation is stability. You have to do your homework to determine how much daily uptake your tank has, adjust the levels to optimum using a 2-part solution and then maintain those levels using any of, or a combination of the methods discussed. It doesn't really matter how you get there, as long as you keep things stable (especially ALK.)

[Chris]

Ok, well I was talking to a good friend today and just happens he has a spare CaRX layin around, and is going to let me try it out......

What all do I need to know/ do to really get it set up and fine tuned for my tank as I dont really know much more then what they do (as far as keeping calcium/alk up and stable

I dont have a ton of coral, but I have a decent amount....
180g display w/ 100g rubbermaid sump and 30g whatever tank attatched, plumbed water flowing but nothing but sand & water in it lol

I have an AC Jr w/1 ph probe