Global CO2 above 400 ppm effect on Reef Tanks

[RenoMark]

I have a question, that may sound political, but I really do not want or intend to get political. So, if you do not believe that CO2 is going up in our atmosphere, please pass this thread. I want to keep this practical and on point about reef tanks.

It is my understanding that average CO2 in our atmosphere has exceeded 400 ppm and in addition, the oceans PH has dropped from 8.2 to 8.1 - I'm assuming that it is the result of this. Feel free to correct me if I am wrong. My question is, will this affect our ability to keep our reef tanks at or near the target of 8.3? It seems that if the oceans PH is dropping to 8.1, to keep a small body of water, such as our reef tanks, at an optimal 8.3 would be nearly impossible without some artificial means.

I have been in the process of building up a tank that has been kept in a stable state for over a year after a crash that involved a leak. I am currently struggling to keep my PH around 8 and above 7.8 at night, far below the ideal 8.2 to 8.3. I have a fuge packed with macroalgae, my skimmer and air comes from outside, and recently I added a CO2 scrubber. I am not asking this question to solve my problems, it may be my tank or process (I will figure it out), I know others do much better and I am not blaming the CO2 in the atmosphere on my problems, but it got me wondering if the challenge is getting harder? And I thought the smart people here might have some interesting input.

Perhaps people could comment on how they solved their PH challenges.

Thanks,

Mark

 

[sundog101]

Generally speaking a co2 increase will decrease ph. So if the gas that's being exchanged through the tank has more co2, you may have low ph problems. You may want to try running your skimmer intake outside (if possible).
If the earth is going to kick the bucket from too much co2 I have no idea, but I guess if it got too high it would affect our tanks. I don't what that number would be though.

 

[GoVols]

Interesting post.
I don't how long this thread will last but I'm tagging along to digest other's incites about the C02 changes in nature in regards to our home's reefs and ph.

 

[bgoldb]

I just recently purchased an awair glow that monitors CO2 as well as VOCs. Based on my observations, my tank ph drops when the indoor CO2 raises above 450. I have recently purchased new bathroom ventilation fans that are extremely quiet. Turning on the bathroom ventilation fans seems to draw more outdoor air into the house and lowers the CO2. I am going to use IFTTT to turn on these fans when the CO2 reading from the air monitoring device raises above 500. I also use a CO2 scrubber connected to the intake of my protein skimmer which raised the pH in my tank .2.

 

[Sabellafella]

I have a question, that may sound political, but I really do not want or intend to get political. So, if you do not believe that CO2 is going up in our atmosphere, please pass this thread. I want to keep this practical and on point about reef tanks.

It is my understanding that average CO2 in our atmosphere has exceeded 400 ppm and in addition, the oceans PH has dropped from 8.2 to 8.1 - I'm assuming that it is the result of this. Feel free to correct me if I am wrong. My question is, will this affect our ability to keep our reef tanks at or near the target of 8.3? It seems that if the oceans PH is dropping to 8.1, to keep a small body of water, such as our reef tanks, at an optimal 8.3 would be nearly impossible without some artificial means.

I have been in the process of building up a tank that has been kept in a stable state for over a year after a crash that involved a leak. I am currently struggling to keep my PH around 8 and above 7.8 at night, far below the ideal 8.2 to 8.3. I have a fuge packed with macroalgae, my skimmer and air comes from outside, and recently I added a CO2 scrubber. I am not asking this question to solve my problems, it may be my tank or process (I will figure it out), I know others do much better and I am not blaming the CO2 in the atmosphere on my problems, but it got me wondering if the challenge is getting harder? And I thought the smart people here might have some interesting input.

Perhaps people could comment on how they solved their PH challenges.

Thanks,

Mark

I think its a great topic. Depending on where you live, your ambient c02 levels can vary often alot shy of 400ppm. I run my skimmer line outside but isnt enuff, so using kalkwasser or any type of lime c02 absorbent works for me.

 

[TbyZ]

I have a question, that may sound political, but I really do not want or intend to get political. So, if you do not believe that CO2 is going up in our atmosphere, please pass this thread. I want to keep this practical and on point about reef tanks.

It is my understanding that average CO2 in our atmosphere has exceeded 400 ppm and in addition, the oceans PH has dropped from 8.2 to 8.1 - I'm assuming that it is the result of this. Feel free to correct me if I am wrong. My question is, will this affect our ability to keep our reef tanks at or near the target of 8.3? It seems that if the oceans PH is dropping to 8.1, to keep a small body of water, such as our reef tanks, at an optimal 8.3 would be nearly impossible without some artificial means.

I have been in the process of building up a tank that has been kept in a stable state for over a year after a crash that involved a leak. I am currently struggling to keep my PH around 8 and above 7.8 at night, far below the ideal 8.2 to 8.3. I have a fuge packed with macroalgae, my skimmer and air comes from outside, and recently I added a CO2 scrubber. I am not asking this question to solve my problems, it may be my tank or process (I will figure it out), I know others do much better and I am not blaming the CO2 in the atmosphere on my problems, but it got me wondering if the challenge is getting harder? And I thought the smart people here might have some interesting input.

Perhaps people could comment on how they solved their PH challenges.

Thanks,

Mark

pH ranges in the oceans from around 7.7 to 8.3 depending on location. Most areas of the ocean pH is very stable, where as other areas pH can vary quite a bit in a short period of time.
As far as pH falling from 8.2 to 8.1, over the last hundred years or so, this is an assumption based on the result of model runs, not actual measured data. Practable & accurate devices to measure the ph of the global oceans has a relative short history. Coral reefs were formed, & have existed through periods when atmospheric concentrations of CO2 were far higher than at present. So don't panic.

CO2 levels in your home, quite possibly, far exceed atmospheric levels, & are at the very least no less. Windows closed, heating on, people breathing all elevates CO2 in indoor areas.

Growing algae in either a scrubber or a refugium will remove CO2 through photosynthesis.

 

[GoVols]

I think its a great topic. Depending on where you live, your ambient c02 levels can vary often alot shy of 400ppm. I run my skimmer line outside but isnt enuff, so using kalkwasser or any type of lime c02 absorbent works for me.

Kalk will get'r done

lol
I still open my windows

 

[GoVols]

I just recently purchased an awair glow that monitors CO2 as well as VOCs. Based on my observations, my tank ph drops when the indoor CO2 raises above 450. I have recently purchased new bathroom ventilation fans that are extremely quiet. Turning on the bathroom ventilation fans seems to draw more outdoor air into the house and lowers the CO2. I am going to use IFTTT to turn on these fans when the CO2 reading from the air monitoring device raises above 500. I also use a CO2 scrubber connected to the intake of my protein skimmer which raised the pH in my tank .2.

This is a repeat from one of my earlier post on another ph thread.

The most hard core ph reefer that I ever read, stated that he hired his local AC company to install small duct work piping from the outside to the squirrel cage fan inside his central heating and air unit. They also put in a small bypass so if it got too cold or too hot he could stop the outside air intake air flow to his unit.

 

[bgoldb]

This is a repeat from one of my earlier post on another ph thread.

The most hard core ph reefer that I ever read, stated that he hired his local AC company to install small duct work piping from the outside to the squirrel cage fan inside his central heating and air unit. They also put in a small bypass so if it got too cold or too hot he could stop the outside air intake air flow to his unit.

I may be going down that road. I'm currently getting proposals for the installation of an ERV which brings fresh air into the house and uses the outgoing air to help heat or cool the incoming air. We'll see. All my money goes to coral or perhaps HVAC.

 

[GoVols]

I may be going down that road. I'm currently getting proposals for the installation of an ERV which brings fresh air into the house and uses the outgoing air to help heat or cool the incoming air. We'll see. All my money goes to coral or perhaps HVAC.

I'm going to call my local HVAC company next week and see if they make them the for split units.

My heat pump compressor unit is outside. The small coils and fan are on the inside of my town home.

 

[Randy Holmes-Farley]

I'm not sure I agree with the premise that the pH "target" is 8.3.

That said, elevating CO2 will lower pH, but it is the indoor CO2 that matters most, typically, and indoor CO2 is greatly elevated in many cases, driving down the tank pH. Often, indoor CO2 gets over 1000 ppm, and smallish changes in the outdoor CO2 level aren't the primary driving factor in the tan pH level.

A doubling in CO2 from 350 to 700 ppm will drop the pH of seawater in equilibrium with it by about 0.3 pH units. So say, from pH 8.2 to pH 7.9.

 

[taricha]

Invariably, when people start measuring pH in tank, they start discussing venting skimmer etc to outdoor air. And it stabilizes and raises their pH.
Is there any reason that would be desirable for anything other than a "better" pH number.
If I'm trying to juice macro-algae growth, would the indoor air be preferable,
and vice versa would venting outside make the water slightly less algae friendly?

 

[TbyZ]

If I'm trying to juice macro-algae growth, would the indoor air be preferable,
and vice versa would venting outside make the water slightly less algae friendly?

Algae! http://reefkeeping.com/issues/2006-10/rhf/index.php

 

[Randy Holmes-Farley]

Invariably, when people start measuring pH in tank, they start discussing venting skimmer etc to outdoor air. And it stabilizes and raises their pH.
Is there any reason that would be desirable for anything other than a "better" pH number.
If I'm trying to juice macro-algae growth, would the indoor air be preferable,
and vice versa would venting outside make the water slightly less algae friendly?

Lower pH likely helps algae.

 

[RenoMark]

Hi Randy, Thank for your response. I had read your article on pH (amongst others of yours) and really appreciate your readable thorough explanations. I also know that you point out that the 8.3 or 8.2 (of seawater) might be hard to achieve and not necessarily optimal (for coral growth) with a reactor, which I do run and achieving good CA & Alk numbers. Although I am still bouncing on the bottom of what you describe as the minimum pH, especially at night. I just found it interesting that as I took steps to change it, they were having little effect. The main change was bring air in from the outside to both my skimmer and to a pump that I use to aerate my affluence from my reactor (something you point out probably does not work), my water change water and my flow from my tank to my sump. I also add Kalk to my top off - mainly at night. And I have a refugium that is lite at night with a lot of macro. These things made little or no difference and that was when I started wondering about the CO2 levels of the outside air and how much of a change the reported raising of CO2 effect us. I do realize that the pH scale is logarithmic and the ppm scale we look at is not, but I honestly do not understand how CO2 is absorbed by water and if it is linear or if there are chemical thresholds that might make it vary... which is probably the case since pH is more about hydrogen. I realize your example (0f 300ppm to 700ppm) is, fortunately, far from a reality for our outside air, but a 300 ppm increase, from us now, making a 0.3 pH change considering it is logarithmic seem significant and significate to what I have read about coral growth. I am still left wondering if an outside change of 300ppm to 400ppm could be making a pH change of 0.1 or 0.2 in the range of pH of 8 in our home aquariums, this to me still means that many of us would have to take bigger steps than just bringing in outside air. But your point that inside levels or more significate make sense. This then raises the question of contact time and quantity - I can bring in outside air, use a CO2 scrubber (which I just did the other day) to reduce CO2 more, but the contact time and quantity of this air has with my water (even though exaggerated by bubble action in the skimmer and such) is short compared to the surfaces of my tank, sump, and refugium contact to inside air.

Randy, I am not asking you to solve my problem, just talking about my process in my head and tank for the thread. I think I am moving in the right direction and think I will have my pH issues resolved soon. I guess as someone that has been keeping reefs for quite a while, but never really paid much attention to pH (at least at a resolution of 7.9 to 8.1), I am amazed at how much effort it does take to maintain my tank at a target pH and wondering what the variables are in that - I like to solve the cause, not make a correction for it. I also find it interesting how much it fluctuates from day to night despite that fact that I am lighting a refugium full of macroalgae for 18 hours. There must be things in my tank that absorbs a lot of CO2 when the lights are on despite not having any macroalgae and having a lot of active critters that are releasing CO2.

I am also interested in hearing how you that are modifying your houses heating system will fair. I can see that in winters, like we are getting now in Reno, the inside CO2 can be a real problem. This Christmas I noticed that my pH had dropped WAY down, it took me a bit to realize we had a group of people over and we were cooking most the day on our gas stove. The next day the tank returned to normal... still lower than I would like, but not the WAY down of the day before. I have been trying to figure out methods of avoiding this.

TbyZ - Keep in mind we are talking about modern adapted corals and optimum growth. Yes, the worlds critters have adapted to many difficult times over long periods of time, but that is not what we are trying to reproduce in our reef tanks. But your point about the change in pH is based on a model is interesting. It does seem, by what I have read, that the worlds major coral reefs are in distress, what would you contribute this to if not pH? Temp, or something else? And is our home aquariums susceptible to the same challenges without new techniques?

bgoldb, I too have a bathroom fan in the room where my sump is, I have it triggered on temperature, but now wounding if I should trigger it on pH or just run it all the time. Might need to get a quieter one.

Thanks for all the feedback!
Mark