I use kalk with a dosing pump (used to use ato). Much easier to control with dosing pump and you don’t ruin your ato pump! Kalk is super useful!
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I think the problem here is using it in ato. Kalk really needs to be added slowly and continually throughout the day. Ato’s add kalk in spurts so you get localized ph spikes in your sump, which causes precipitation and makes it appear like the kalk isn’t keeping up....which tricks us into adding other stuff like soda ash (bad idea) or bicarb to compensate. How do I know this? Because I added kalk via ato and had the same issues with precipitation. I got rid of that system and for a while was adding saturated kalk solution through a jebao dosing pump (one channel on a dp4) twenty four times a day. Precipitation stopped and I was easily maintaining 9dkh vs the 7dkh I was consistently getting with ato-added kalk. Had I not switched to a CalRX, I’d be running a Kamoer fx-stp and a brute can full of saturated kalkwasser.
Yep, full saturation.Ok so I can do this easily as I have two unused dosing pumps but how satrurated can I make the kalk solution? Just 2 tablespoons per gallon right? I like this idea, thanks.
Your alk may have continued to climb because there is lower demand now that Kalk is not being dosed? lower pH? just my thoughts.
Im dosing kalk via my GHL doser so we'll see how long it lasts
No. Two TEASPOONS per gallon. 2 tablespoons will be 3 times what you need per gallon. Some do less, like 1 - 1.5 teaspoons per gallon, depending on how saturated you want your limewater to be.Ok so I can do this easily as I have two unused dosing pumps but how satrurated can I make the kalk solution? Just 2 tablespoons per gallon right? I like this idea, thanks.
Yes, I saw that on the bottle when I actually did it. Thank you!No. Two TEASPOONS per gallon. 2 tablespoons will be 3 times what you need per gallon. Some do less, like 1 - 1.5 teaspoons per gallon, depending on how saturated you want your limewater to be.
Well he is still dosing 2 part, I believe. So he many need to adjust his 2 part dose to his new (lower) consumption level.There certainly may be lower demand at lower pH, but normally alkalinity does not rise unless it is added somehow.
Well he is still dosing 2 part, I believe. So he many need to adjust his 2 part dose to his new (lower) consumption level.
we definitely are lol. I wasn't paying attention to the dates.I think we were talking about different people. The OP hasn't been in the thread for 5 months. I thought you were referring to oysterjake who revived it.
Just wanted to revive this old valuable thread. Lots of experienced reefers dose kalkwasser in the ATO so I am trying to replicate as a newer reefer.
Within 3 months my Tunze 3155 optical sensor failed due to grime on the sensor which almost resulted in my Vectra return pump running dry. This, and now reading that the dosing line can clog, ATO pumps fail more quickly, and so on has me thinking 2 part might be lower maintenance and higher precision in the long run.
That said, I’ve modified my ATO setup with kalkwasser so it adds upstream of the return chamber and before the bubble trap mechanical filter. Hopefully this helps a bit.
Any other tips for using Kalkwasser to minimize risk? Thank you
After the discussion here and research, I've gone to a DIY Kalk stirrer. Works really well, much cleaner, and easier on equipment.
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Thank you. My understanding was that surface precipitation/grime was inevitable in kalkwasser solutions (could be wrong; definitely not mixing optimally). I’m dosing at the low end for calcium hydroxide using the BRS website (1/2 tsp per gallon I recall).You can add Kalkwasser with a dosing pump so the pump is not submerged in kalkwasser.
The real main issue is the ATO pump getting all calcified up. Also not having a bunch of unused kalkwasser floating around the ATO container.
You can use a dosing pump and a separate container from your ATO to dose Kalk same as two part.
You also can use a kalk stirrer also.
You should not have anything on the sensor in your sump from dosing alk unless you have precipitation. In that case you are adding to much Kalkwasser.
PS - I think one of the reasons my Tunze 3155 optical sensor was compromised is because I let the Tunze auto dose immediately after mixing a new solution and before precipitate had settled.Thank you. My understanding was that surface precipitation/grime was inevitable in kalkwasser solutions (could be wrong; definitely not mixing optimally). I’m dosing at the low end for calcium hydroxide using the BRS website (1/2 tsp per gallon I recall).
I like the idea of using a multi-head doser and trickling kalkwasser (or maybe just sodium hydroxide) alongside 2 part.
My naive understanding of kalk stirrers is that they can be costly and add more maintenance / specialization in the long run (things I’m trying to minimize as this is a work tank).
Cheers and thx for the thoughts.
FWIW, I think using kalk and 2-part, if additional supplementation is needed, is a great solution.I use kalk with a dosing pump (used to use ato). Much easier to control with dosing pump and you don’t ruin your ato pump! Kalk is super useful!

