Adjusted alkalinity (down) in new sea water with HCl

[Rick.45cal]

So I adjusted my waterchange water's alkalinity down using HCl because it mixed very high. I brought 30 gals down 1 dKh using 3ml of HCl. The vat has a powerhead and I have also added an air pump and air stone. The pH tests at 7.8. My question is, can I expect it to rise on it's own? Is there a better/faster way to get the pH to rise?

My concern is I have some frags coming tomorrow and I don't want to drop the pH of the display when I replace the few gallons I will pull from the display for dipping and rinsing frags. Thanks in advance!

 

[jason2459]

How big is the display? What does your tank normally run for pH? What is your tank's alkalinity levels and the new saltwater's level? I would not worry that a small water change will alter your tank's pH or alkalinity very much.

 

[Rick.45cal]

The total system water volume excluding sand and rock is about 600L (160 gallons roughly). Tank tests at 8.09 dKH (Hanna) and the new saltwater is at 8.5 dKh now. (It was 9.8 dKh). I generally keep the tank around 7.5 dKh so I was trying to avoid a big alkalinity spike when I do a waterchange later in the week. It had slipped my mind about the frags coming tomorrow and needing some saltwater. My tanks pH generally gets down to 7.9 at night and goes up to 8.3-8.4 by the end of the day.

 

[Randy Holmes-Farley Verified Community Expert]

Aeration will boost it ONLY if the water has excess CO2 in it relative to the ambient air. At pH 7.8, it may not if you have elevated CO2 in the air.

There's no way to raise it in this situation except aeration with lower CO2 air.

 

[Rick.45cal]

Aeration will boost it ONLY if the water has excess CO2 in it relative to the ambient air. At pH 7.8, it may not if you have elevated CO2 in the air.

There's no way to raise it in this situation except aeration with lower CO2 air.

Thanks Randy! That's the answer I was expecting to receive!