When do you add more calcium hydroxide to Kalk stirrer?

[Randy Holmes-Farley Verified Community Expert]

This was a great rabbit hole to go down. Lots of great information. I'd love to find the solution as to why the Kalk reactor doesn't hold saturation like a reservoir. You all have great hypotheses, though.

Lack of saturation would simply be that the reactor is not dissolving it as fast as new water is entering. It's not really a hypothesis, more like a truism.

I'm under the impression that alk levels are dependent on pH and vice versa; higher pH allows more soluble alk to be available in the water column. When you're dosing Kalk and having pH fluctuations, how big are the swings between the 2 and what is truly acceptable? We're reaching a point where our scientific understanding is great, so would chasing a fairly stable pH be the best way to nail stable alkalinity?

That first sentence is not true. Higher pH does not allow more alk to be available.

Kalkwasser and other hydroxide additives are simply a high pH alk additive.

As to whether it is better to have more stable alk or more stable pH, or both, you might read through this thread:

Alkalinity stability? pH stability? Are they even different?

It is currently the dogma of the reef aquarium hobby to say that alkalinity stability is very important for SPS corals, and that pH is not. Often, the very idea of someone trying to optimize pH is called “chasing numbers” as if that statement by itself shows it to be foolish. Since I have...

www.reef2reef.com

 

[Operator Wrasse]

Lack of saturation would simply be that the reactor is not dissolving it as fast as new water is entering. It's not really a hypothesis, more like a truism.



That first sentence is not true. Higher pH does not allow more alk to be available.

Kalkwasser and other hydroxide additives are simply a high pH alk additive.

As to whether it is better to have more stable alk or more stable pH, or both, you might read through this thread:

Alkalinity stability? pH stability? Are they even different?

It is currently the dogma of the reef aquarium hobby to say that alkalinity stability is very important for SPS corals, and that pH is not. Often, the very idea of someone trying to optimize pH is called “chasing numbers” as if that statement by itself shows it to be foolish. Since I have...

www.reef2reef.com

Believe it or not, I've read through your work several times, but there's so much to unpack at once. I'm finding missing pieces every time I read and I'm grateful that we have someone like you for our hobby. Thank you for everything you've done for the reefing world.

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome and thanks!

Happy Reefing!

 

[Rocco89]

Sorry for hijacking this thread I’m new to the game and new to kalk stirrers, I just got myself a octo stirrer and having trouble dosing it seems like it’s not strong enough in potency.. I’m using the seachem kalk I now got myself a hm ec pen to check the potency what numbers should I be aiming for? Thank you

 

[Randy Holmes-Farley Verified Community Expert]

Sorry for hijacking this thread I’m new to the game and new to kalk stirrers, I just got myself a octo stirrer and having trouble dosing it seems like it’s not strong enough in potency.. I’m using the seachem kalk I now got myself a hm ec pen to check the potency what numbers should I be aiming for? Thank you

What units does the pen read in?

Saturation is about 10.3 mS/cm, and the potency is about linear with the conductivity. You may not need saturation, however, and with some stirrers it can be hard to attain or control.

 

[Rocco89]

What units does the pen read in?

Saturation is about 10.3 mS/cm, and the potency is about linear with the conductivity. You may not need saturation, however, and with some stirrers it can be hard to attain or control.

It read us/cm. Ms/cm. Ppm . Yea I’m finding it hard to keep a stable range in the stirrer because every time you open the top to measure the stirrer agitates the kalk on the bottom I got a reading of this .. seems to be holding my alk now.. as before I went my seachem instructions and the 2 teaspoon was never going to be potent enough that’s wat had me scratching my head. This is my current reading

 

[Koigula]

I really think this whole thread is making a simple technique complicated. Stirrers are under saturated and that is fine if consistent.

Mechanical equipment failures are more of a concern to me. I used the OSC function on a Neptune, A BRS 50 cc/min doser for 2 min on / 2 min off every 20 minutes at night and 15 gallon carboy to the doser feeding a K1 stirrer. It does fine but needs to be inspected daily with rest of system for less than 10 minutes.

If I advanced, oddly I would get rid of the Avast K1 stirrer and just add saturated kalk to carboy directly. Current set up seems less messy for now.

 

[Rocco89]

I really think this whole thread is making a simple technique complicated. Stirrers are under saturated and that is fine if consistent.

Mechanical equipment failures are more of a concern to me. I used the OSC function on a Neptune, A BRS 50 cc/min doser for 2 min on / 2 min off every 20 minutes at night and 15 gallon carboy to the doser feeding a K1 stirrer. It does fine but needs to be inspected daily with rest of system for less than 10 minutes.

If I advanced, oddly I would get rid of the Avast K1 stirrer and just add saturated kalk to carboy directly. Current set up seems less messy for now.

I’m only asking cause I’m new to kalkwasser and kalkwasser stirrers hence why I’m asking about it… I just wanted to know the right numbers I should be aiming for in my stirrer and any other tips .

 

[Randy Holmes-Farley Verified Community Expert]

I’m only asking cause I’m new to kalkwasser and kalkwasser stirrers hence why I’m asking about it… I just wanted to know the right numbers I should be aiming for in my stirrer and any other tips .

Saturation is about 10.3 mS/cm at 25 deg C. Half that is half potent.

Half potent may be all you need. For years I used less than full strength limewater (kalwkasser) in my system.

 

[tikireefer]

Has anyone done the Zip Tie trick on the Avast K1 or K2 to see if it helps? Just curious if anyone has any feedback on this. Thanks!

 

[Randy Holmes-Farley Verified Community Expert]

What is a zip tie trick? lol

 

[tikireefer]

oof, I spoke to Avast they suggested I put zip ties up the shaft.. Guess we'll see how that works. Worse case I dedicate more space to a 50-gallon container but I'd like to avoid that if possible.

Hey Randy.....yeah doesn't sound very scientific does it.... lol

I guess Avast had suggested putting zip ties on the shaft of their stirrer to help with saturation issues. Kind of like little stirring fins to help keep it mixing all the way up the reactor, not just stirring at the bottom???

 

[Randy Holmes-Farley Verified Community Expert]

Hey Randy.....yeah doesn't sound very scientific does it.... lol

I guess Avast had suggested putting zip ties on the shaft of their stirrer to help with saturation issues. Kind of like little stirring fins to help keep it mixing all the way up the reactor, not just stirring at the bottom???

Oh, I get it. I've never used something like that but it is sensible.

 

[tikireefer]

I think I am going to try it on my K1 and see what happens..... a pretty easy hack! lol

 

[14 foot reef]

I added a few model airplane props to my K2 stirrer, I for sure notice a difference in the saturation of the solution. the cloudy solution is also visually higher in the reactor. I bought 4 props and installed one, then eventually added a second. I'm happy with the results of this mod

 

[tikireefer]

I added a few model airplane props to my K2 stirrer, I for sure notice a difference in the saturation of the solution. the cloudy solution is also visually higher in the reactor. I bought 4 props and installed one, then eventually added a second. I'm happy with the results of this mod

That is really cool! Great idea!

 

[Reef370]

I added a few model airplane props to my K2 stirrer, I for sure notice a difference in the saturation of the solution. the cloudy solution is also visually higher in the reactor. I bought 4 props and installed one, then eventually added a second. I'm happy with the results of this mod

Do you have a link to the ones you used? And did they fit directly or did you have to modify them in any way? Thanks

 

[14 foot reef]

Do you have a link to the ones you used? And did they fit directly or did you have to modify them in any way? Thanks

I just went to a hobby shop that specialized in airplane models they had 10,000 of them on a wall i just grabbed a few different ones as they were like $2.00 a piece. I did have to enlarge the hole for the shaft to fit, but simple drill worked perfect

 

[Reef370]

I just went to a hobby shop that specialized in airplane models they had 10,000 of them on a wall i just grabbed a few different ones as they were like $2.00 a piece. I did have to enlarge the hole for the shaft to fit, but simple drill worked perfect

Thank you sir!! I’m on it!