Effect of skimmer on ph

[VegasReefer]

this is a hilarious conversation.... you actually think you can use a formula to evaluate CO2 in a reef constantly? good luck with that.... unless you have a meter to understand the different CO2 output in your environment, i don't know how you can come to that conclusion, but more power to you.

There's also the assumption that the pH swings are from photosynthesis alone . No pets, people, appliances in the house?

Yes, a skimmer will absolutely change gas exchange in a reef,,,, different skimmers will have different gas exchange. Even the same model skimmer will have different gas exchange throughout the year. Even dosing into a sump with a different skimmer will effect pH by means of precipitation.

 

[arking_mark]

Again this is simple. If a tank was completely aerated(at equilibrium with room air) we would not have ph swings(assuming stable alkalinity). I dont need an explanation of why it is not always at equilibrium as that is my entire point here. Your entire premise(his co2 would have to be 2100) is assuming his tank is at equilibrium.

You are now posting articles that negate your premise by showing that processes within the tank that impact co2 cause ph to go up and down(again precisely because it does not stay at equilibrium)

Or said another way.....it is very possible that processes within his tank have increased co2 levels above what they would be if they were at equilibrium with his room co2.

How? What would drive CO2 levels higher than equilibrium with the air?

Answer:
1. Inadequate aeration.
2. Livestock respiration
3. Another source that increases CO2

#2 is usually countered by #1 and besides a Calcium Carbonate reactor there's not much being used to lower pH.

So generally speaking CO2 levels higher than equilibrium are unlikely and most tanks go from that pH floor of equilibrium to something higher based on photosynthesis and other ph-raising methods.

Please provide other pH lowering mechanisms that will lower pH beyond air equilibrium (main source of CO2) that are significant.

 

[arking_mark]

this is a hilarious conversation.... you actually think you can use a formula to evaluate CO2 in a reef constantly? good luck with that.... unless you have a meter to understand the different CO2 output in your environment, i don't know how you can come to that conclusion, but more power to you.

There's also the assumption that the pH swings are from photosynthesis alone . No pets, people, appliances in the house?

Yes, a skimmer will absolutely change gas exchange in a reef,,,, different skimmers will have different gas exchange. Even the same model skimmer will have different gas exchange throughout the year. Even dosing into a sump with a different skimmer will effect pH by means of precipitation.

Alk, pH, and tank CO2 have a well defined mathematical relationship. Given ANY pH and Alk reading anyone can calculate the effective tank CO2 levels.

A well aerated tank without pH lowering additives will almost certainly have a pH at or above the air CO2 equilibrium.

 

[mdb_talon]

How? What would drive CO2 levels higher than equilibrium with the air?

Answer:
1. Inadequate aeration.
2. Livestock respiration
3. Another source that increases CO2

#2 is usually countered by #1 and besides a Calcium Carbonate reactor there's not much being used to lower pH.

So generally speaking CO2 levels higher than equilibrium are unlikely and most tanks go from that pH floor of equilibrium to something higher based on photosynthesis and other ph-raising methods.

Please provide other pH lowering mechanisms that will lower pH beyond air equilibrium (main source of CO2) that are significant.

Why on earth would i need to provide more examples. You just did so yourself.

It is far from accurate to assume tanks are completely aerated(again if they were we would not have a ph swing both co2 production and consumption eithin the tank would be equalized by that aeration!)

Livestock does have respiration...or can we not use this one for some reason also? Co2 is a waste product of metabolism.

Calcium reactors are common in the hobby...but you ignore that one as well.

Again you make this blanket statement about with no disclaimers that it must be measurement error when we certainly dont know that.

I will say I went back and read the first link you posted in this thread and am even more convinced because Randy called you out on your assumptions also and I am confident he knows more about this than either of us

 

[arking_mark]

Why on earth would i need to provide more examples. You just did so yourself.

It is far from accurate to assume tanks are completely aerated(again if they were we would not have a ph swing both co2 production and consumption eithin the tank would be equalized by that aeration!)

Livestock does have respiration...or can we not use this one for some reason also? Co2 is a waste product of metabolism.

Calcium reactors are common in the hobby...but you ignore that one as well.

Again you make this blanket statement about with no disclaimers that it must be measurement error when we certainly dont know that.

I will say I went back and read the first link you posted in this thread and am even more convinced because Randy called you out on your assumptions also and I am confident he knows more about this than either of us

Great we agree.

 

[VegasReefer]

Alk, pH, and tank CO2 have a well defined mathematical relationship. Given ANY pH and Alk reading anyone can calculate the effective tank CO2 levels.

A well aerated tank without pH lowering additives will almost certainly have a pH at or above the air CO2 equilibrium.

tank CO2 yes, but without knowing the surrounding CO2 levels how do you determine a solution...

Anyways wasn't this a simple question of if a skimmer could effect pH.... just saying.... thanks for the entertainment

 

[arking_mark]

tank CO2 yes, but without knowing the surrounding CO2 levels how do you determine a solution...

Anyways wasn't this a simple question of if a skimmer could effect pH.... just saying.... thanks for the entertainment

You're welcome.

A skimmer will work to drive pH to equilibrium with the CO2 in the air it is pulling in.

Per the original poster, this is outdoor air and probably around 400matm.

With an 8.12dKH for tank Alk, it's trying to drive the tank to a pH of 8.27 NBS.

This is probably competing against the powerheads, return pumps, and sump aeration with the usually higher CO2 indoor air.

Assuming no other significant CO2 contributors and that switching skimmers lowered pH. This skimmer may be less effective.

Assuming normal indoor CO2 levels, if pH readings go below 7.8, then overall aeration may be inadequate.

Performing a cup aeration test will confirm this issue.

If cup aeration test doesn't show this issue, then I would suspect the accuracy of the pH measurements.

 

[Randy Holmes-Farley Verified Community Expert]

I have been using a royal exclusiv vertex alpha 200 skimmer with an outside airline connected to it. My ph used to be in the 7.90-8.15 range. The skimmer pump broke and I replaced it with a red sea 600 skimmer. Now the ph is at 7.65‐7.80. Alk is at 8.12.

My question is, can skimmer have such an impact on ph? Or could there be something else that is affecting the ph in addition to skimmer change?

A skimmer can raise or lower pH, depending on the pH, alk, and the CO2 level in the air used.

That said, a skimmer itself cannot lower pH that is already below 8, unless the air entering it has a substantially elevated CO2 level in it.

Switching between two skimmers can raise or lower pH (or both at different times of day), depending on how well the two skimmers aerated the water.

 

[arvind]

7.65pH is most likely a measurement error.

If you pH is less than 7.8, your pH meter is probably wrong

Post in thread 'Aquarium pH Distilled' https://www.reef2reef.com/threads/aquarium-ph-distilled.853474/post-9330359

www.reef2reef.com

Your CO2 level around the tank/skimmer would need to be 2100.

Long-term exposure to this level would effect your health.

Right on. The ph probe is faulty. I switched to an old ph probe and now it reads 8.08.

Just to clear the air (pun intended), I tried the newer skimmer with both outside air and inside air. The ph remained the same.

I also measured using a 7 calibration solution and it showed 6.98. So I assumed the ph probe is fine. Then I posted here looking for answers and after seeing your comment I decided to switch to old ph probe and now it is reading correctly.

Great discussion.

 

[arking_mark]

Right on. The ph probe is faulty. I switched to an old ph probe and now it reads 8.08.

Just to clear the air (pun intended), I tried the newer skimmer with both outside air and inside air. The ph remained the same.

I also measured using a 7 calibration solution and it showed 6.98. So I assumed the ph probe is fine. Then I posted here looking for answers and after seeing your comment I decided to switch to old ph probe and now it is reading correctly.

Great discussion.

I'm like a broken clock. Only right twice a day.

 

[vetteguy53081]

The typical pH of a reef tank will vary over the course of a day, but it will have an effect on how efficient the skimmer is. At the peak of the day when the pH is the highest, your skimmer will foam the most since the electrostatic attractions and affinity of organic molecules to the bubbles will increase.
To make your skimmer more efficient, you should try to keep your pH between 8.0 and 8.3. The more stability that the pH has with stable alkalinity , the longer the foam head will stay and the more particulate matter will form.

 

[arking_mark]

The typical pH of a reef tank will vary over the course of a day, but it will have an effect on how efficient the skimmer is. At the peak of the day when the pH is the highest, your skimmer will foam the most since the electrostatic attractions and affinity of organic molecules to the bubbles will increase.
To make your skimmer more efficient, you should try to keep your pH between 8.0 and 8.3. The more stability that the pH has with stable alkalinity , the longer the foam head will stay and the more particulate matter will form.

Wow. I learn something new everyday. Do you have a reference for that info? I'd like to read up on that. Thanks in advance!

 

[vetteguy53081]

Wow. I learn something new everyday. Do you have a reference for that info? I'd like to read up on that. Thanks in advance!

Skimmer causing pH to DROP

How is this possible? Everyday I turn my skimmer off for a few hours. When I turn it back on after a few hours I notice that the pH actually DROPS. I have a Neptune pH probe and it is calibrated. This happens while the lights are on, so it isn't just a coincidence that the pH is dropping as...

www.reef2reef.com

 

[Randy Holmes-Farley Verified Community Expert]

At the peak of the day when the pH is the highest, your skimmer will foam the most since the electrostatic attractions and affinity of organic molecules to the bubbles will increase.

Some will, some just the opposite. It depends entirely on the nature of the organics involved.

I know it has been said by some over the years that higher pH helps skimming, but I've never seen any evidence or demonstration of it.

A skimmer foaming more at a specific time of the day might just as easily reflect processes in the tank that are adding skimmable molecules.

 

[SDK]

Just to clear the air (pun intended), I tried the newer skimmer with both outside air and inside air. The ph remained the same.

Depending on where in the US you live this is not surprising for the month of October, where temps are moderate just about everywhere.

I'm in New England and am able to get fresh air into the house most of the year. As soon as I seal everything up and turn the oil burner on, my PH drops. Running my skimmer line outside for those three months makes a difference. I snake a 30' foot line around behind my sectional sofa and out a window so the air can warm up a bit before it reaches the skimmer. I had a short line through the wall at one time, but the extreme cold temps where I live got the skimmer cold enough to cause condensation, and have it acting almost as a chiller.

Although I have no direct experience with it, I would imagine those living down south get this in a reverse schedule when they seal up and put on the central AC...

 

[Randy Holmes-Farley Verified Community Expert]

Although I have no direct experience with it, I would imagine those living down south get this in a reverse schedule when they seal up and put on the central AC...

Yes, they do. Many reports here of that.