PH High

[gliebig]

I'm not sure why my PH is reading high. I am on a well which tests neutral from the hose.
My pond is ~7,500 gallons. I had it filled from a pool company/pumper truck last fall. This spring, I drained a good bit and filled it with my well water ~5k gallons worth. I test my PH from the pond and it's 8+. I have no idea why.
It is currently under renovation. We haven't done any rock work yet, just a new liner.

 

[Smaug]

The pH usually goes down over time.

 

[gliebig]

The pH usually goes down over time.

I'm just not sure why it is 8+ when I filled it with water that tests neutral?

 

[sissy]

8 it is normal not high .Mine stays at 8 all the time and as long as it is stable it is fine

 

[Smaug]

Water can test quite different from tap to a standing state after being exposed to air. My water will come out if faucet right around 8 then stabilize to mid 7s after a few hours.

 

[gliebig]

Water can test quite different from tap to a standing state after being exposed to air. My water will come out if faucet right around 8 then stabilize to mid 7s after a few hours.

Funny. Mine is the opposite. Comes out as 7 then stabilizes at 8+. Same water for over a month. I tested again tonight and it's still 8+

 

[MitchM]

When you aerate water with splashing or aeration, the PH will typically rise because CO2 is equalized with ambient air.
Less CO2 = higher PH, generally.

 

[gliebig]

I do have four airstones in there.

 

[MitchM]

That's a good thing.

 

[cas]

When you aerate water with splashing or aeration, the PH will typically rise because CO2 is equalized with ambient air.
Less CO2 = higher PH, generally.

Interesting!

 

[Meyer Jordan]

What MitchM states is true, but Co2 levels will stabilize regardless of aeration. While it is not unusual for pH to drop a full point or more, it is highly unusual for pH to rise a full point or more. Do you have any limestone rock exposed to the water? That might account for part of the rise.

 

[gliebig]

What MitchM states is true, but Co2 levels will stabilize regardless of aeration. While it is not unusual for pH to drop a full point or more, it is highly unusual for pH to rise a full point or more. Do you have any limestone rock exposed to the water? That might account for part of the rise.

No limestone. I posted some pics in this thread.
https://www.gardenpondforum.com/threads/new-guy-pond-redo.19028/
Everything is covered by liner and built in drains around the pond. Shouldn't have anything getting in there.

 

[Meyer Jordan]

How would you rate the algae growth on the liner----none, slight, moderate or heavy. I have a reason for asking?

 

[gliebig]

None to slight.

 

[Meyer Jordan]

Do you know what your Dissolved Oxygen level is?
I am going through a process of elimination here.