Kalkwasser and Alkalinity

[migs]

Is kalkwasser a CA and Alk supplement? Or just CA?

And what is the difference between kalwasser and kalkwasser mix?

[Timfish]

Calcium only. "And what is the difference between kalwasser and kalkwasser mix?" I tend to use the terms interchangebly but some aquarists may refer to one as the clear water used to add to a tank and the other as the cloudy mix that needs to settle. A CO2 reactor with shells, crushed coral or a specific reactor media is balanced for calcium and alkalinity. This doesn't mean processes in your tank can't contribute to an imbalance. pH, alk and calcium need to be monitored periodicly even if you use the ol' eyeball like I usually do.

[migs]

Thank you... I always heard Kalk was for alk... But wen I started reading labels and searching... I found it was CA only.

[+mcallahan]

Kalk raises your alk as well. Read this, (paraphrased below)

"The kalkwasser solution contains water, calcium ions and hydroxide ions. The calcium ions obviously help to raise the concentration of calcium in the water, a good thing for animals and plants that use calcium for their skeletons. The hydroxide interacts with dissolved carbon dioxide to form bicarbonate, and together with any remaining hydroxide ions, this raises the alkalinity, thereby buffering pH and inhibiting acidification."

I was able to hold off dosing Alk for a long time by using kalk. Now that my corals are growing so fast, I've had to start dosing alk even though I'm still using kalk.

[migs]

I was wonder about that... A calcium reactor is just calcium substrate and Kalk is calcium carbonate. I guess I will try it.

[don duncan]

Just to add to what Mark said. It does dose Alk and Ca

I run a 280 sps dominant tank. I was using a CA reactor for years. My colonies have gotten pretty big and suck up CA.

Several moths ago I added a kalk reactor to help keep the CA and Alk up. It also helped stabalize my Ph.

Kalk also has the added benefit of reducing phosphates.

[Timfish]

Mark, that's a really good article for people to start with, thanks for posting it. Migs, I would encourage you to also read the references Mr. Shultz provides links to. If you go back a couple of layers you'll come across a reference to an article by Randy Holmes-Farley that helps solve alk & calcium problems you may want to bookmark. (Here's the link but I reccommend reading the articles in the chain to get to this reference: http://www.advancedaquarist.com/2002/11/chemistry.) If you want more detail on how the calcium hydroxide reacts with CO2 in your tank to form carbonate and bicarbonate I would suggest reading ch 5 of Delbeek and Sprung's "The Modern Reef Aquarium" Vol III. It's curious to note while Randy Holmes-Farley refers kalkwasser/limewater as a balanced supplement while Delbeek and Sprung make a point a ballanced supplemnt may need to be used in conjunction with it. It's my understanding the alkalinity associated with kalkwasser/limewater is the caustic alkalinity of the calcium hydroxide and is not the carbonate or bicarbonate alkalinity that we need to maintain in aquariums. These are formed by chemical reactions in our tanks and are affected by variables in out tanks and at least initially need to be monitored closely.