pH help with 4 g Pico

[PiscesPower]

I started a 4 g pico last week. Using a rock and water from my 24g DT, pH in DT is 8.34 using Seneye Reef monitor. Alk @ 10 Ca 450, Mg 1340. All this week the pH in the pico has been 7.8 -7.9. I have put the Seneye in there to monitor. I did use new sand, small bit, maybe a pound. No ammonia issues. I do have what appears to be some diatoms. I have a Kessil A80 on it and temps running 79 - 80.

Not sure how to get the pH up without boosting Alk higher. I did my H2O change with Instant Ocean instead of Red Sea Reef since I really just have a few little corals in the pico. They are doing fine. Only livestock is an Emerald crab about 1" and a single hermit crab.

I put an airstone in the back to try and reduce pH that way, but to no avail after a day or so. I have 2 pumps moving H2O so that should not be an issue.

Any insight would be helpful. Its my intent to bring it to work next week, but I want to be sure its stable. I predict I will be able to keep the temp a bit cooler as the ambient there is about 70 , whereas at home its a bit warm this week. Not sure if that matters.

 

[Fitzreefer]

Is it in the same room of your home?

 

[Fitzreefer]

Meaning, are both tanks in the same room?

 

[PiscesPower]

They are, however I do have a protein skimmer in the DT sump doing lots of gas exchange.

 

[Fitzreefer]

That eliminates the possibility of CO2 build up in the air of a particular room. Did you check the calibration of the pH probe? What are the other params of the Pico?

 

[Randy Holmes-Farley Verified Community Expert]

The pico will respond to elevated room CO2 a lot faster than a larger tank, so it may be due to room CO2.

There really isn't any other possibility aside from high CO2 somehow (except pH measurement error or alkalinity super low).

 

[Fitzreefer]

The Alk is where I was leaning, but I don't think we got full params for the Pico. I figured unless an outside intake or scrubber was employed on the DT, that it would have a low pH too if located similarly.

 

[Randy Holmes-Farley Verified Community Expert]

For a pH of 7.8 to be in equilibrium with normal air, the alk would need to be well below 4 dKH.

 

[Fitzreefer]

Or maybe test error or out of calibration. Is there possibly something in the room that could produce higher CO2 locally to the Pico placement.

 

[PiscesPower]

it seems to have settled after a week or so and a few water changes. Its now running at 8.3 like my main tank.

Thanks for the input

 

[Randy Holmes-Farley Verified Community Expert]

Good to hear.

Happy Reefing.

 

[Katrina71]

More tank pics please