Can we talk PH?

[805hd]

The Ph in my 170 gallon is always on the rise. I’m not falling into the whole going insane chasing my PH cause it MUST be exactly where I want it routine. But, I would like to know why.

Out the tap,

PH- 7.4
AMO- 0
N02- 0
N03- 0
GH- 8*
KH- 4*

Out the tank,

PH- 8.0
AMO- 0
N02- 0
N03- 10-20 (using ferts for plants)
GH- 8*
KH- 4*

As you can see, the ph creeps up 0.6 points. I tried to recreate this in a bucket with an air stone for 24hrs and had no fluctuation. Something in the tank is changing things.

The substrate is pool filter sand and the rocks are fake. All my plants are real. I do keep discus so my water sits around *84-*85 degrees.

The sump is pretty basic, the media consists of sponge and ceramic rings/ blocks. Running a large air stone and a sponge filter in there.

The tank is tall so there is quite a bit of vertical fall for the water to travel. Between that, the overflow, the sump, air stone and the two returns pointing at the surface I’m sure I’m getting more than enough aeration and gas exchange.

Could this amount of off gassing have anything to do with my PH rise?

I’m okay with the numbers, the tank seems to be stable. I just don’t like unknown variables. Not knowing why this is happening is driving me crazy. I know I’m over looking something.

Anyone?!

 

[tlindsey]

The Ph in my 170 gallon is always on the rise. I’m not falling into the whole going insane chasing my PH cause it MUST be exactly where I want it routine. But, I would like to know why.

Out the tap,

PH- 7.4
AMO- 0
N02- 0
N03- 0
GH- 8*
KH- 4*

Out the tank,

PH- 8.0
AMO- 0
N02- 0
N03- 10-20 (using ferts for plants)
GH- 8*
KH- 4*

As you can see, the ph creeps up 0.6 points. I tried to recreate this in a bucket with an air stone for 24hrs and had no fluctuation. Something in the tank is changing things.

The substrate is pool filter sand and the rocks are fake. All my plants are real. I do keep discus so my water sits around *84-*85 degrees.

The sump is pretty basic, the media consists of sponge and ceramic rings/ blocks. Running a large air stone and a sponge filter in there.

The tank is tall so there is quite a bit of vertical fall for the water to travel. Between that, the overflow, the sump, air stone and the two returns pointing at the surface I’m sure I’m getting more than enough aeration and gas exchange.

Could this amount of off gassing have anything to do with my PH rise?

I’m okay with the numbers, the tank seems to be stable. I just don’t like unknown variables. Not knowing why this is happening is driving me crazy. I know I’m over looking something.

Anyone?!

View attachment 1558383

Possibly the plant fertilizer is causing the PH to rise because may contain alkaline salts and minerals in the ingredients.

 

[805hd]

Possibly the plant fertilizer is causing the PH to rise because may contain alkaline salts and minerals in the ingredients.

I thought about that. Entirely possible, I’m using easy green from aquarium co-op. I looked online but didn’t see much about it. I know they have good customer service. Maybe I’ll ask them directly.

Thanks!

 

[duanes]

In some cases water under pressure in the distribution system has concentrated gases such as CO2, but is relased quickly when pressure is released, causing the lower pH when tested soon after leaving the tap, sometime giving an initial skewed reading.
When in your tank however, the natural buffers (alkalinity/calcium/bicarbonates) in the water take over, raising pH to the actual water parameters in yout natural water, "if" those buffers are concentrated enough.
You could check you EPA water quality section, or ask your water supplier about the alkalinity concentration (natral buffers) in your water source.
Or test it yourself with an alkalinity test strip, or liquid test.

When I lived in Wisconsin water (after treatment and sequestered in the pipes) from the tap, gave a reading of bout 7.5, but in acuality lake Michigan water was highly buffered naturally and had a pH of 8.4, so once in the tank rose a bit.

 

[805hd]

duanes You’re saying it could be a source issue? Wouldn’t I have seen that change when I did the bucket test after 24hrs though?

 

[duanes]

duanes You’re saying it could be a source issue? Wouldn’t I have seen that change when I did the bucket test after 24hrs though?

Maybe 24 hours is enough, maybe not.
An alkalinity test is a way to be sure,
its interesting because your water tests if accurate (KH 4 and GH 8) are considered fairly soft

Are their some species you want to keep that you are worried about?

 

[805hd]

duanes well I currently have 4 discus in the tank. I understand stable parameters are better than fluctuating parameters.. It's weird, I just did a random PH test and it came back at 7.4.... lol what the heck is going on here?! I know I'm testing correctly, only change I made since yesterday's test was turning off the airstone in the sump!

I'm really beginning to think that is has something to do with having ample agitation. That or my plants are playing games with me.

 

[805hd]

On the left is water from the tank on the right is water from the tap. Tank sample is darker, but it was even darker on previous tests. Almost perfect match to 8.0. Even closer with a white background behind it.

Maybe my eyes are just cooked from years of welding…

 

[neutrino]

duanes You’re saying it could be a source issue? Wouldn’t I have seen that change when I did the bucket test after 24hrs though?

Are you aerating the bucket? If not that could be the difference.

It's not an uncommon phenomenon. My pH out of the tap is about 6.6 (it can vary a bit) and always settles at 7.4 in my tanks. Inert sand substrate and rocks, well water with enough natural buffering that adding a couple of almond leaves or a newly collected driftwood piece doesn't affect it.

 

[duanes]

To me that brown doesn't like pH 8, maybe closer to 7.4.
Here are a pH test I read as 8 ish.