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.

 

[allof fish]

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.

I do have a little less coral along with the lighting schedule which I know will affect it a bit. I would love to push it up a little higher if I can consistently be around 8.2-8.3. Not dead set on doing everything possible to get to 8.3 or higher unless I start dosing kalk which I’m not now. I run brs 2 part which what I’ve found is one of the highest ph solutions being soda ash. Grabbing air outside isn’t attainable at the moment. Just tryna to pick ideas about how to raise jt

 

[BryanM]

Is it the same size scrubber for the now much larger tank?

 

[allof fish]

Is it the same size scrubber for the now much larger tank?

Yes it is. In my research a larger one won’t necessarily make ph higher. Will make media last longer and can improve airflow thru the scrubber. So I don’t believe getting another one or larger one would make a huge difference. I opened a few windows nearby to see if that helps. Kalk might be a better long term solution

 

[Randy Holmes-Farley Verified Community Expert]

I do have a little less coral along with the lighting schedule which I know will affect it a bit. I would love to push it up a little higher if I can consistently be around 8.2-8.3. Not dead set on doing everything possible to get to 8.3 or higher unless I start dosing kalk which I’m not now. I run brs 2 part which what I’ve found is one of the highest ph solutions being soda ash. Grabbing air outside isn’t attainable at the moment. Just tryna to pick ideas about how to raise jt

You could switch to a diy or commercial hydroxide-based two part.