Kalkwasser Precipitating and causing low Alk

[DIYReefGuy]

Hey there, my Kalkwasser is precipitating in my sump and causing all the walls to turn white. I just started dosing it in my sump right next to the overflow drain. I scraped the sides of the sump and within 3 days its back to being cloudy and then will eventually turn all white again.

What steps do i need to take? Any amount of 2 part also seems to make the situation worse as now my alk is at 5.3dkh.

My corals look ok with polyp extension but id rather not have them in low alk. Im thinking putting in a cheap powerhead where the kalk doses and hopefully it stops precipitating and boosts the alk back up naturally.

let me know your thoughts

 

[Miami Reef]

Here's my generic advice for such scenarios:

1. Stop all efforts to boost pH.
2. Stop dosing alk for a bit and let it decline.
3. Reduce pH by switching to a low pH alk mix like sodium bicarbonate, or a calcium organic such as Tropic Marin All for Reef.
4. Ensure magnesium is normal to high.
5. Keep organics and phosphate on the high side.

After a few days of not dosing alk, restart slowly, adding additives to a very high flow area so it mixes in fast.

Click on Randy’s name in the quote to go to the original thread he posted this message.

 

[Randy Holmes-Farley Verified Community Expert]

Hey there, my Kalkwasser is precipitating in my sump and causing all the walls to turn white. I just started dosing it in my sump right next to the overflow drain. I scraped the sides of the sump and within 3 days its back to being cloudy and then will eventually turn all white again.

What steps do i need to take? Any amount of 2 part also seems to make the situation worse as now my alk is at 5.3dkh.

My corals look ok with polyp extension but id rather not have them in low alk. Im thinking putting in a cheap powerhead where the kalk doses and hopefully it stops precipitating and boosts the alk back up naturally.

let me know your thoughts

In addition to the above info on how to avoid precipitation, how are you dosing the kalkwasser? How much each day/ How fast? How do you make it?

 

[DIYReefGuy]

currently, i mix about 12 gallons in a Food safe container to full saturation, then i use a BRS 50ML/Minute doser to dose Kalkwasser every time the PH drops below 8.2. Based off the run time, i estimate im adding about 2-2.5 gallons of Saturated Kalkwasser to the system a day

 

[DIYReefGuy]

Click on Randy’s name in the quote to go to the original thread he posted this message.

Thank you!

 

[DIYReefGuy]

In addition to the above info on how to avoid precipitation, how are you dosing the kalkwasser? How much each day/ How fast? How do you make it?

Also quick question on the above. if my alkalinity is already below 6dkh, would stopping Alk dosing and Kalk dosing harm the coral with the additional drop

 

[Sisterlimonpot]

Another clarifying question, is there a reason why you're dosing 2 part and kalk?

 

[DIYReefGuy]

Another clarifying question, is there a reason why you're dosing 2 part and kalk?

Yes because the Kalkwasser is not keeping up with the alkalinity, I initially started because i saw the alk drop below 7dkh and its been steadily declining since

 

[Randy Holmes-Farley Verified Community Expert]

Is the alk currently below 7 dKH?

I'd stop dosing the kalkwaser and just dose two part, and I'd dose only a low pH two part for a while (such as made with baking soda/sodium bicarbonate).

 

[DIYReefGuy]

yes its at 5.6 dkh with the lowest being at 5.2. thank you so much!

 

[Jamie814]

I'd stop dosing the kalkwaser and just dose two part

I definitely 2nd this, I was having the same issue, trying to get ph up with kalk, it was causing a bunch of precip which just required more and more 2 part. I just stopped dosing kalk and backed off on the 2 part and got ca/alk back into a stable balance.

 

[Eienna]

Question. What is your magnesium level? I believe that being too low can cause precipitation, as the mag prevents the calcium and alk crystals from binding together.

 

[Jamie814]

my mg was steady at about 1400

 

[Eienna]

my mg was steady at about 1400

OK, then I imagine that's not the issue.

 

[Eienna]

I believe I was hearing that you can't let the pH in the section you're dosing to get over a certain point...maybe too much is getting dosed at once, or it's not moving through fast enough? Try putting the pH probe in the same compartment, so that it shuts off before it gets that high. Also, I believe you're supposed to be dosing to raise to an alk point, not a pH point.

EDIT: I believe it is also recommended to dose next to your return pump, but I'm not sure...?