Salt Change Impact

[spsick]

@Randy Holmes-Farley , is there any way to calculate how much an impact on pH and dosing will have switching to a high cal / all salt will make?

Switching from Red Sea blue bucket to Reef Crystals, and I change 15g/week on AWC on a 130g reef.

My reef’s params mirror the blue bucket,
420 calcium
8.0 dkh
1350 magnesium

where the reef crystals are
550 calcium
10.9 alk
1440 mag

I am thinking ok great, I can use less 2 part (I am using your 2 part + part C) and kalk but how much less can hurt pH enough?

Dosing 85ml/day soda ash and 1L overnight of kalk.

 

[Randy Holmes-Farley Verified Community Expert]

One can estimate.

Any effect on pH is negligible.

An 11.5% water change with a 10.9 dKH salt mix and a tank at 8 dKH will boost alk from 8.0 dKH to 8.33 dKH.

That’s a nearly insignificant boost of 0.05 dKH per day if done once a week. Equivalent to about 5 mL per day of the alk part.

 

[spsick]

One can estimate.

Any effect on pH is negligible.

An 11.5% water change with a 10.9 dKH salt mix and a tank at 8 dKH will boost alk from 8.0 dKH to 8.33 dKH.

That’s a nearly insignificant boost of 0.05 dKH per day if done once a week. Equivalent to about 5 mL per day of the alk part.

Thank you Randy, that makes me feel much better about it!!

 

[BryanM]

Thank you Randy, that makes me feel much better about it!!

Isnt alk consumption going to stay the same? You're just changing the overall parameters of you water by moving to a different salt, but I think alk demand stays the same.

Maybe I'll learn different shortly :)

 

[Randy Holmes-Farley Verified Community Expert]

Isnt alk consumption going to stay the same? You're just changing the overall parameters of you water by moving to a different salt, but I think alk demand stays the same.

Maybe I'll learn different shortly :)

If you do water changes with a mix higher than the tank, each change acts like a bit of dosing. :)

Ultimately, if the tank comes up to match the new salt water, then you are right, no boost. But that is unlikely to happen since alk demand rises as alk itself rises. :)