Low ph. Tried the basics

Well my new tank is 6 days old! Shrimp is rotting and cycle has started and life is good!



Ran some tests today and all was good save my ph. It's 7.62Checked my other tank and got 7.77. Knowing that lighting plays a role in ph I turned the lights on for a couple hours and saw 7.79. I know the tank is new but my other tank is established. I think I should get the ph up to at least 8



Ro/di Water is 0 tds mixed with RC salt to 1.025

Temp 78.6

PH 7.79 tested with API (not quite to 7.8 color) and new, calibrated PH meter.

Ammonia 0.5 - 1.0ppm

Nitrite 0ppm

Nitrate 0

Calcium 480-520

dkh 8 or 145ppm

Phosphate <0.25ppm.

Mag 1350



Performed "outside air test " to check for co2 issues-no change in reading

Tank is open top



My question is: How should I go about raising my ph?



I don't think calcium reactor is the answer given my calcium is high already, but my alkalinity could use a bump as we'll

Do I add baking soda? Or vodka? Ph buffer? Never dosed anything so I'm clueless.



The tank is 45g, 40lb base rock, 30g sump with air powered skimmer. Will house softies but would like some LPS in the future.