Ph question

[allof fish]

In my old tank with a co2 scrubber I would consistently hit 8.3-8.4 everyday and at night it would drop to between 8.1-8.15ish. That tank was around 80g total volume. In this new tank it struggles to reach 8.15 peak. I changed my scrubber to recirculating to try and help. I also changed my light schedule to 2hrs less since the tank is new which I can will affect it a little. This is is closer to 175-180g total volume. Is the larger water volume a reasonable explanation? Or is the scrubber not as effective currently? Any other explanations and how I can try to raise it up more?

 

[Randy Holmes-Farley Verified Community Expert]

The aeration of the larger tank may be less (or more) effective, impacting how well CO2 is drawn in or pushed out. Less photosynthesis per gallon and per tank top aeration also plays a big role, so it's not just the lighting but the nature and number of the organisms present.

I would not assume the pH needs to be raised, but if you want it higher, sending outside air to your scrubber may help, as can using higher pH alkalinity additives when you need them. Fresher air to the room may also help, at least at night.