trouble with pH in hot humid weather

[wjgeese]

I have my air intake plumbed to the outdoors to try to keep my pH in a reasonable range, but in thenl summer I really struggle to get it over 8 esp when it's hot and humid...typically ranges from 7.6 to 7.9, but when a cold front comes trhough, bringing cooler temps with low humidity it jumps to 7.9 to 8.2. Why would this be?

 

[Pickle_soup]

I have my air intake plumbed to the outdoors to try to keep my pH in a reasonable range, but in thenl summer I really struggle to get it over 8 esp when it's hot and humid...typically ranges from 7.6 to 7.9, but when a cold front comes trhough, bringing cooler temps with low humidity it jumps to 7.9 to 8.2. Why would this be?

In warmer temperatures, the air is thinner, so you are sucking in fewer molecules.

 

[sc50964]

How is your alk?

 

[jda]

Even with an outside air intake, the co2 in your home is the largest factor in tank pH. Do you open the windows up more during those cool, dry times?

 

[wjgeese]

In warmer temperatures, the air is thinner, so you are sucking in fewer molecules.

It's just hard to believe that it would impact the ph so much though. Seems that plumbing the intake to outside on the summer is worse than leaving it to suck air from inside the house. crazy

 

[Pistondog]

As @jda said, likely when hot and humid, ac is on, windows closed, co2 levels rise, whicn lowers ph.

 

[wjgeese]

Even with an outside air intake, the co2 in your home is the largest factor in tank pH. Do you open the windows up more during those cool, dry times?

Good point. Didn't consider that.

 

[Pistondog]

Co2 levels are the main cause of low ph in our hobby.

 

[wjgeese]

As @jda said, likely when hot and humid, ac is on, windows closed, co2 levels rise, whicn lowers ph.

yeah, I guess I thought that plumbing the skimmer outside would help offset that. guess not. lol

 

[jda]

The outside air to the skimmer helps, but think of it like trying to breathe through a drinking straw rather than taking a full breath. You want the drinking straw over nothing, but unobstructed breathing is way better.

The great thing about your area is that with 60s at night, you can always air out your home. We run an attic fan nearly every night in Colorado and keep our co2 in the 400s and the tank pH is always good.

 

[Pistondog]

yeah, I guess I thought that plumbing the skimmer outside would help offset that. guess not. lol

It does help. Skimmer and surface adgitation, both contribute to gas exchange.
Id guess ph would be lower if skimmef sourced inside air

 

[jda]

The only way to really know is to get an indoor co2 meter. They are not too expensive on Amazon. Under 700ppm is usually fine. Over that and the tank pH starts to rise.... and it can do so significantly quickly. The lower co2 air is good for the humans and pets too.

 

[Randy Holmes-Farley Verified Community Expert]

In warmer temperatures, the air is thinner, so you are sucking in fewer molecules.

That may or may not happen, but the effect is not big enough to explain those pH differences. A difference of 0.3 pH units means half as much CO2 is in the water.

 

[Randy Holmes-Farley Verified Community Expert]

I agree with folks that the effect, if not random testing error, is an indoor CO2 issue.

FWIW, even in a closed home, the air turnover rate increases as the temp difference between inside and outside increases.

 

[ShoreReefer]

This shows what happened when I opened the windows in the house a few weeks ago. You can see the PH rising and at the same time Alk going down hoping it means that the corals were consuming more Alk.

 

[wjgeese]

Well, I bought a co2 meter on Amazon. My inside co2 is 1400ppm! Holy cow!!! Now what to do...whole house air exchanger? Wife is not pleased.

I never realized how much air echxange from the surface of the tank cam influence pH, above and beyond have a skimmer plumbed outside. crazy.

 

[PeterErc]

I have the skimmer plumbed outside as well. Often consider connecting the overflow standpipe vents as well. I don’t monitor ph so I don’t know if that will help. House is closed up most of the year, keep on truckin

 

[jda]

Open a few windows for a few minutes each day in the morning when it is cool - one on each side to let the air pass through. If the wind is blowing, it will move a lot of air in - a 3x4 window with even a 1 mph wind moves at 88 feet per minute or 1056 cubic feet with barley any wind. With the meter you can see how much this changes the reading. You will need the AC to run for a while to mix the house air up for a while.

 

[wjgeese]

Open a few windows for a few minutes each day in the morning when it is cool - one on each side to let the air pass through. If the wind is blowing, it will move a lot of air in - a 3x4 window with even a 1 mph wind moves at 88 feet per minute or 1056 cubic feet with barley any wind. With the meter you can see how much this changes the reading. You will need the AC to run for a while to mix the house air up for a while.

I did this already...didnt change the levels in the room more than 50ppm or so. looking into air exchanger. thanks

 

[CJ13]

I have my air intake plumbed to the outdoors to try to keep my pH in a reasonable range, but in thenl summer I really struggle to get it over 8 esp when it's hot and humid...typically ranges from 7.6 to 7.9, but when a cold front comes trhough, bringing cooler temps with low humidity it jumps to 7.9 to 8.2. Why would this be?

I just read about CO2 and humidity, I’m have humidity issues in my house and lower ph levels in my aquariums, says higher relative humidity causes higher CO2 levels, I just recently purchased a dehumidifier and once I get it setup and running and drop humidity then I want to see if that actually helps with the ph