Calcium Reactors ???

[NAS]

The Calcium reactor also dissolves the other elements locked up in the coral. This includes your strontium, mb, Carbonate, Calcium, and every thing else. EXCEPT Iodine.

the Kalkawaser is only Calcium hydroxide, so it's strictly calcium. It also jacks your ph wich in turn causes swings in pH. If not done correctly this can cause big trouble.

[fkshiu]

Waay back when before the two-part method and reliable calcium reactors pretty much all old school reefers had was kalkwasser. I found with my old 46 gallon that it does provide both Ca and Alk, but it can't keep up with much demand since it is evaporation limited.

I use kalk now simply to keep pH up at night.

[NAS]

The bottom line comes down to your needs. If you are cool running suppliments you have to add Kalkawaser and Carbonate buffer. At different times.

One for Calcium (kalk) one for KH (carbonate buffer). There is no way around it. Best to do it at different times to avoid precipitaion of Calcium Carbonate.

The calcium reactor is like a constant feed of both. Keep in mind if you don't de-gas enough you can have pH issues with a reactor as well. An answer to an earlier query, you really don't want or need to direct feed to your return pump. It won't de-gas the reactor effluant and probably have too high of feed rate. Resulting in an over dose of KH and Ca2+

[Reefer Rob]

Never had a calcium reactor... never wanted one. High Ca/kH demand, SPS tank. Automate you 2 part (3 part), it's the easiest way!

[StirCrazy]

just a note, you can use your return pump to feed the Ca reactor, but not all the return can go through it. you just "T" off the return side with a 1/4" line and a valve to regulate how much you are supplying.

[reefermadness]

This is from Randy's Article -- What your Grandmother never told you about limewater


What Is Lime?

According to the National Lime Association, “lime” is defined as either quicklime or hydrated lime. These materials are made by heating calcium carbonate until the carbon dioxide is driven off, forming quicklime (calcium oxide):

1. CaCO3 à CaO + CO2

Water can then be added to form hydrated lime (calcium hydroxide; referred to subsequently in this article as just lime):

2. CaO + H2O à Ca(OH)2

Both lime and quicklime are suitable for making limewater (kalkwasser) and otherwise supplementing calcium and alkalinity in reef aquaria. There are some important differences between the use of lime and quicklime that will be discussed in subsequent sections. These differences relate to the fact that quicklime is slightly more potent and gets hot when water is added to it (equation 2).

http://www.reefkeeping.com/issues/2005-01/rhf/index.php

I've never known that limewater only supplies calcium is a common misconception?

[Oxymoron]

Lots of great info in this thread thank you all.
Would anyone know of a particular reactor with a very small footprint yet still suitable for a 90 gal tank? Im hoping on having a combination of softies and sps.
Thanks
Oxy

[StirCrazy]

Originally Posted by reefermadness

I've never known that limewater only supplies calcium is a common misconception?

It should be that it does a better job of supplying Ca than it does Alk, and in a high usage tank it won't keep up as it is only added by make up water. but in the same turn, if you have a tank that the alk is stable but the Ca drops then it works.

the biggest advantage to the Ca reactor is that it buffers the Alk way better and can maintains it slightly elivated compared to Ca.

I used to run my alk at 12dkh as I found once I got above 11 my colors just popped. when I took my Ca reactor off line for a redesigning, my Kalk reactor couldn't keep up on its own with 7 gals per day of make up water in a 120 gal system. This was a high consumption tank with extreamly fast SPS growth.

now having said all this, in one tank it might work perfectly, where the other it may not, every tank is different, and what works for one won't nessasarly work for another.

Steve

[sphelps]

neither a Ca reactor or a Kalk reactor will add a perfectly balanced amount of both Ca and Alk.

Calcium reactors increase alkalinity more than calcium and as a result you'll probably always find yourself having to dose a calcium additive or maintain a higher than normal alkalinity.

With Kalkwasser or Calcium Hydroxide it's the opposite. It will increase calcium more than alkalinity. So when using Kalk you'll likely always find yourself having to add a buffer to maintain your alkalinity. However calcium hydroxide does not directly add carbonate, it adds hydroxide which is not used by corals. The hydroxide however will react instantly with carbon dioxide to form carbonate. This is why many people using Kalk will have a difference in opinion on how much it is actually buffing their water.

For these reasons many of us believe the obvious solution would be to run both systems, however this will probably only work for a high demand system and could be difficult to tune to your tank's requirements. The obvious solution to me would be to use neither and employ a system which adds the exact amount of each in a balanced amount to meet your system requirements.