Oh V/S Alk

[Erikpanzer]

I’m having trouble with my KH. I am using RO water when I make new saltwater, but when I add marine buffer the KH shoots way up also. I can’t seem to find that balance where I can keep a 8.3 PH and not have the KH go through the roof. I did a 20 gal water change last weekend and I bought 20 gallons of premade water from my LFS. After it ran for about 6 hours I tested Ph and it was at 8.0 with a KH of 8. I added just a teaspoon of buffer to get 8.3 and the KH shot up to 14. It’s like I can’t get one without jacking up the other. Any help would be appreciated

Thanks Erik
120 gal
I’m using Seachem buffer
Temp 78
Salt 1.024
PH 8.3
Ammonia.02
No2 .01
No3 .05
Phos .08
Cal 19 = 380
Mag 1280
KH 11 right now

 

[kharmaguru]

Marine buffer products ARE alkalinity. You should target an alkalinity and stay there. Don't use it for PH control.

PH is always going to swing and trying to keep it pegged will make you crazy. It's high during the day because of biological processess and low during the night when photosynthesis stops.

You can mitigate the swings somewhat by:

Increasing surface motion.
Running your skimmer airline to draw outdoor air ( I do this)
Putting a CO2 scrubber on your skimmer
Runnning a refugium or algae scrubber at night opposite your tank lights.
Using kalkwasser in your top off water.

 

[Erikpanzer]

Marine buffer products ARE alkalinity. You should target an alkalinity and stay there. Don't use it for PH control.

PH is always going to swing and trying to keep it pegged will make you crazy. It's high during the day because of biological processess and low during the night when photosynthesis stops.

You can mitigate the swings somewhat by:

Increasing surface motion.
Running your skimmer airline to draw outdoor air ( I do this)
Putting a CO2 scrubber on your skimmer
Runnning a refugium or algae scrubber at night opposite your tank lights.
Using kalkwasser in your top off water.

Ahh, thanks for the info. Makes a lot of sense now.