Ph and water volume.

[joekidwell]

I upgraded tanks from an 25 gallon aio to a 65 gallon. With the 25 gallon I was able to keep the ph pegged at 8.3 easily with my co2 scrubber but since I upgraded I'm having a hard time getting past 7.92 with my alkalinity at 8.0 I'm still using the skimmer from my old tank rated for 75 gallons. Will upgrading and oversizing my skimmer allow me to get back to 8.3?

 

[Miami Reef]

I upgraded tanks from an 25 gallon aio to a 65 gallon. With the 25 gallon I was able to keep the ph pegged at 8.3 easily with my co2 scrubber but since I upgraded I'm having a hard time getting past 7.92 with my alkalinity at 8.0 I'm still using the skimmer from my old tank rated for 75 gallons. Will upgrading and oversizing my skimmer allow me to get back to 8.3?

Is there a way you can recalibrate your pH probe just in case it’s giving a false low reading after the upgrade?

The only other explanation I can think of is that CO2 is entering from the surface agitation from the display. Maybe there wasn’t that much surface agitation in the 20 gal?

Or maybe there‘s some sort of processes in the new tank (recently cycled?) that’s causing the pH to be lower?

 

[mdb_talon]

What u describe makes complete sense. The more air you put through the scrubber into the tank then yes the more likely your pH will go back up, but would just be a wild guess as to how much you would have to upsize it.

 

[joekidwell]

Is there a way you can recalibrate your pH probe just in case it’s giving a false low reading after the upgrade?

The only other explanation I can think of is that CO2 is entering from the surface agitation from the display. Maybe there wasn’t that much surface agitation in the 20 gal?

Or maybe there‘s some sort of processes in the new tank (recently cycled?) that’s causing the pH to be lower?

I can recalibrate it as soon as the calibration solution is back in stock.

I always make a point to agitate the surface as much as possible, in the 25 I used the two return nozzles and the mp10 helped some, in the 65 I'm using a gyre along with the return.

As for the cycle its been up and running since early September, everything was transferred from the old tank except for the sand.

 

[mdb_talon]

I always make a point to agitate the surface as much as possible, in the 25 I used the two return nozzles and the mp10 helped some, in the 65 I'm using a gyre along with the return.

Assuming your co2 in the room is relatively high then more agitation offsets some of the impact of the co2 scrubber. The co2 scrubber takes co2 out, but all that surface agitation is putting it back in. Surface agitation obviously does other things as well and I still think it good to have, but now with a bigger surface area tank and the co2 scrubber can't keep up.

 

[joekidwell]

The DFC 180 showed up today good thing too because after 3 years the ol 1.5 hob pump gave out yesterday. Just enough room for me to remove the cup lol. It's installed and breaking in, well see of it helps with the ph, I've had the windows open for a few hours but with no skimmer the ph is at 8.0