Question about Kalk in ato

[VegasUSP]

I am about to start using Kalk in my ato, I use a brute trashcan as my resevior and plan on building a stand for my pump to raise it above the slurry. How tall should I make my stand? More specifically how thick does the slurry get? Thanks!

[fourzero]

you wouldn't want to fill a brute trashcan with kalk, as it is exposed to the air the calcium reacts with CO2 and CaCO3 precipitates. This is why you see much, much smaller kalk reactors.

Of course, if you are running a system of several thousand gallons and are replacing 20+ gallons a day, this might be necessary.

[VegasUSP]

I had been told earlier that if I keep it covered I should be fine, I was just planning on drilling a hole in the cover for the tube.

[fourzero]

told by who? Some guy at your LFS? Unless the container is airtight, you are getting CO2 in there from the air, and your kalk is precipitating out and becoming useless. Even if you could somehow get it airtight, you'd have to have a vent of sorts to pump anything out of it.

You will exhaust your kalk and waste time and money trying this.

[VegasUSP]

From a different thread:

Just keep the inlet tube a few inches off the bottom . A rigid tube works easily. Let the kalk settle after stirring it in for about 2 hours before startingthe pump.. then you'll get only clear kalk water. Keep it unstirred in a covered container( not necessarily sealed). It won't loose it's strength unstirred for weeks to a month or so; maybe longer.

http://reefcentral.com/forums/showthread.php?t=2177431&highlight=kalk

Per Randy Holmes-Farley

Referring to Kalk in ato

"This type of limewater system is the type that most often comes under fire for being prone to degradation problems by reaction with atmospheric carbon dioxide. In this type of system, limewater is made up once, and then allowed to sit unstirred for as long as it takes the delivery system to send it to the aquarium. Since this type of reservoir can deliver limewater to the aquarium for several weeks, many aquarists have incorrectly concluded that substantial potency is lost as the limewater degrades, and that such a system will fail. Moreover, this assertion is why many aquarists claim that Nilsen reactors are simpler: because the simple delivery from a large reservoir won't work and that only daily mixing of limewater can be successful. In truth, it takes me five minutes to make up limewater every 2-3 weeks, so the idea that some other system is easier to use is simply unfounded. Later in this article I will show that such simple systems do not lose substantial potency, and hence should be considered by aquarists who have the space for large reservoirs."

http://reefkeeping.com/issues/2003-05/rhf/feature/index.php

[VegasUSP]

I have seen people say that it needs to be sealed but there is no way that all the people out there using kalk via ato have completely airtight containers. Do you dose kalk via ato? If so, what container are you using? Not trying to be a smart *** i'm just curious so I can possibly go buy one myself lol.

[fourzero]

"Since calcium carbonate is not an effective supplement of calcium and alkalinity in reef aquaria, the limewater can become less useful through this process. The rate at which this happens in large containers, such as plastic trashcans with loose fitting lids, is much less than many aquarists expect. There is, in fact, little degradation under typical use conditions."

http://reefkeeping.com/issues/2003-05/rhf/feature/index.php

I can tell you from my experience, I only get about 2 weeks before the pH of the lime starts dropping rapidly. It then becomes a question of whether you want to haul a large trashcan around with a bunch of kalk or just pull a smaller reactor. Whatever works for you.

[bertoni]

I kept limewater for weeks in loosely-covered containers with no appreciable degradation in strength. These were still reservoirs, with no pump or the like.