Calculating water volume based on 2 Alk measurements and dosing amount?

[reefiniteasy]

So I just completed my tank transfer and calculated my water volume at 32 gallons as I did the transfer.
I just measured my alkalinity and it was 7.7dKH. I keep my tank at 7.9dKH. That’s the number I shoot for and I dose ESV 2-part in equal amounts based on alkalinity.
I measured 7.7dKH and used the Reef Chemistry Calculator and it said to dose 3ml to raise to 7.9dKH. After testing again, I overshot and measured, 8.0dKH. No big deal. That does however mean my water volume calculation of 32 gallons is off. Is there a way to calculate my actual water volume based on my two measurements and what I dosed? Thanks!

 

[Randy Holmes-Farley Verified Community Expert]

IMO, the uncertainty of alk measurements is way too crude for this to be a very accurate volume measurement. But in principle, the method is sound. If you routinely overshoot, using a lower water volume is appropriate.