I'm totally over dosing 2 part I'd like to start using Kalkwasser via my ro/di top off. I use a 5g bucket to store my top off water in. Is there a time limit on storing the prepared kalk water? I will not be using an ATO.
I believe you need to store kalk enhanced FW in an airtight container... I could be wrong though. If that's the case then I'd recommend having a "kalk top off jug" in addition to the 5 gallon bucket. Just use a gallon vinegar (or whatever) bottle to mix the kalk in. Then do something like a 50/50 blend of bucket top off and kalk top off.
Jamie - In some ways, Kalkwasser (Calcium Hydroxide) can be simpler than 2-part...
It's a "balanced" solution, meaning it adds Ca and Alk in the same proportion as as corals uptake (only one thing to dose.)
It can be kept indefinitely in a still, tightly covered bucket. Just make sure there is some extra, undissolved Kalk in the bottom of the bucket. After time, you may notice a hard "skin" (Calcium Carbonate) form on the top of the Kalk solution. This occurs when the Kalk solution is exposed to CO2 and creates a barrier that limits further degradation. For these reasons and the high pH, it's best to use a pump rather than constantly opening and closing the bucket to dose manually.
Some also believe Kalk also has the benefit of being able to precipitate out Phosphates.
The drawbacks are similar to 2-part (at least the Alk component) in that Kalk when fully saturated has a pH above 12 and must be dosed/dripped slowly.
When used in ATO, your Ca and Alk dosing is tied to your evaporation rate. Depending on how many stony corals you have in your tank, this might be more or less dosing than is needed and can result in too high (or low) Ca and Alk levels.
Kalk doesn't provide as much Alk and Ca as can 2-part. High demand tanks will reach a point that Kalk dosing alone cannot keep up with the Ca/Alk demands. At that point the addition of 2-part or a Calcium Reactor is needed.
You also have the option of adding Kalk using a dosing pump (as opposed to using kalk-saturated ATO.) This give you the ability to control ALK/Ca dosing independent of your evaporation rate and you can dose overnight to counter your tanks diurnal pH swings.
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man. - George Bernard Shaw
[*]When used in ATO, your Ca and Alk dosing is tied to your evaporation rate. Depending on how many stony corals you have in your tank, this might be more or less dosing than is needed and can result in too high (or low) Ca and Alk levels.
This is very true. I just started dosing kalk with my ATO through a Kalk stirrer and the first time I used a little less kalk powder than what the driections said to use, just in case. The next day my dKH shot from 8ish to 13 Lucky there wasn't a major PH swing and I was checking my levels every 12 hours so I was able to get it back down to 10. But I have to use significantly less then the recomended amount, if you do start using kalk keep a close eye on your levels when first starting out until you find the dose that works for you.
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