Massive Air!! My Experience with Outdoor Aeration, pH boost, & Stability

[Northern Flicker]

What are the signs that your coral are unhappy with a lower pH?

What are the signs that raising your pH is working?

I currently have a pHthat goes from 7.8-8.1. I am happy with my tank's performance and the growth in my stonies but who knows - maybe it could be improved this way?

It's just me and my wife in our house and the tank is in a very drafty basement so I am thinking co2 is not a driving factor. Maybe switching to DIY kalk would be a better first step.

Thanks for the great post OP!

 

[rishma]

Did not have time to read past first three pages but seems to me that the key is gas exchange improvements to expel co2 quickest. Not sure how that helps if room co2 is high and gleaned off the fact room co2 through scrubber showed improvement as did getting outside air. In other words, reducing amount of co2 introduced regardless if less laden outdoor air or scrubbed indoor was key. Perhaps rate of co2 pushed out faster than co2 pushed back in naturally by equalizing with room co2 at tank surface. At least how my brain is making sense of it.

Large air stone driven by most powerful air pump the solution

I think the first post is really all you need to read, if anything.

But yes powerful air pump with outdoor air driving a large airstone has the biggest impact on pH for my tank.

 

[bubbgee]

I have an interesting observation to share. My pH has been peaking somewhere a bit above 3.35 +/- . The pH rise would slow down or flat line toward the end of the light cycle. It also fell very quickly in the first few hours after the light was off.

Yesterday I turned off the air pump at 6PM and the pH rose higher and faster than it usually does in the last few hours of the light cycle.



I left the air pump off for the first few hours after the lights went out. The pH fell more slowly.

I think without the aeration, photosynthesis is driving the CO2 lower in the water and the resulting pH is higher. I suspect photosynthesis drives CO2 in the water lower than the equilibrium amount with the outdoor air. At some point toward the end of the light cycle, the aeration was pushing the pH lower by actually increasing the CO2.


I don’t know that any of this matters!

Corals all seem happy, honestly independent of the pH on a given day. My PH was much lower for a few days when I had the air pump turned off. Corals looked exactly the same. I think growth is higher with higher pH because alkalinity consumption is up over the last couple of months. Other than that, I am not convinced higher pH makes corals happier but I’ll stay with it anyway.


If I could plug it into my apex, I’d have the air pump turn on when pH dropped below a certain point.

I have noticed that effect on my end as well. I was now setup my apex to turn off aeration as my light schedule peaks and turn it back on when I hit 8.0 pH. My objective right now is to cap the bottom range of my pH around 7.95

 

[bubbgee]

I expect that is true. Aeration can raise or lower pH, and can do opposite things at different times of the day.

Whaaaa???

I thought pushing O2 will bump up pH. Is it a temperature thing or just plain light cycle?

 

[rishma]

What are the signs that your coral are unhappy with a lower pH?

What are the signs that raising your pH is working?

I currently have a pHthat goes from 7.8-8.1. I am happy with my tank's performance and the growth in my stonies but who knows - maybe it could be improved this way?

It's just me and my wife in our house and the tank is in a very drafty basement so I am thinking co2 is not a driving factor. Maybe switching to DIY kalk would be a better first step.

Thanks for the great post OP!

I really don’t know what the signs are that lower pH is making corals unhappy. I’ve always thought higher pH was better, but I cannot honestly say I have healthier corals at 8.3 than I did at 8.1. They do seem to grow faster, but that may or may not be something people want

One benefit I do see is alkalinity is more stable now, I think because the pH is more stable and the swings more consistent. Before, my tank’s pH would vary significantly with windows open vs closed. I think this would cause alkalinity consumption to vary and I had to adjust my dosing more often.

That said, I also have no evidence the variation in alkalinity was making anything unhappy. It’s just less work for me to keep it stable.

 

[rishma]

Whaaaa???

I thought pushing O2 will bump up pH. Is it a temperature thing or just plain light cycle?

It’s all about how much CO2 is in the water.

If photosynthesis is pulling CO2 levels in the water lower than aeration, aeration would cause pH to go down. Looking at my graphs, this probably only happens at higher pH in my tank

 

[rishma]

I expect that is true. Aeration can raise or lower pH, and can do opposite things at different times of the day.

I guess if I take a cup of water and aerate outside and measure pH, that will tell me what the equilibrium pH with outdoor air is. If I wanted to be really cleaver, I’d have aeration turn on/off at that point. Below that pH aeration is helping and above that the aeration is actually pushing pH down.

Edit: I am going to do that. My guess is it’s 8.33 based on the graphs. Documenting my guess here…will report back

 

[Randy Holmes-Farley]

I guess if I take a cup of water and aerate outside and measure pH, that will tell me what the equilibrium pH with outdoor air is. If I wanted to be really cleaver, I’d have aeration turn on/off at that point. Below that pH aeration is helping and above that the aeration is actually pushing pH down.

Edit: I am going to do that. My guess is it’s 8.33 based on the graphs. Documenting my guess here…will report back

More than anything, I think it will be a test of your pH measurement accuracy. lol

 

[rishma]

More than anything, I think it will be a test of your pH measurement accuracy. lol

How dare you!

 

[GARRIGA]

I think the first post is really all you need to read, if anything.

But yes powerful air pump with outdoor air driving a large airstone has the biggest impact on pH for my tank.

But is that mostly because gas exchange expelling co2 faster than equalization with room co2?

I say this because (if I read it correctly) you saw an improvement when running indoor air through a scrubber. Not saying better than outdoor but better than doing neither outdoor or indoor scrubbed.

 

[rishma]

But is that mostly because gas exchange expelling co2 faster than equalization with room co2?

I say this because (if I read it correctly) you saw an improvement when running indoor air through a scrubber. Not saying better than outdoor but better than doing neither outdoor or indoor scrubbed.

Yes. That’s is what’s happening. The outdoor air aeration is driving CO2 out of the water faster than it can enter the water from the higher CO2 indoor air.

The main reason I prefer this over a scrubber is it requires little/no maintenance. Both are achieving the same goal.

 

[bubbgee]

I guess if I take a cup of water and aerate outside and measure pH, that will tell me what the equilibrium pH with outdoor air is. If I wanted to be really cleaver, I’d have aeration turn on/off at that point. Below that pH aeration is helping and above that the aeration is actually pushing pH down.

Edit: I am going to do that. My guess is it’s 8.33 based on the graphs. Documenting my guess here…will report back

Hi @rishma, can you please share your apex code for this? Would like to see how it compares to mine. I am setting my point at 8.25 (based on my dosing regimen at peak light and pH). With my code, I am trying to slow down the drop of pH in the middle of the night to my baseline of 8.0. My dawn light turns on at 6am where I've seen it drop to its lowest point and this is where I kick off some photosynthesis to keep it at 8 and prevent it from dropping further. I do a dose of kalk to restore it back to 8.2 around 9am.

airpump schedule:

Fallback OFF
Set OFF
If pH < 8.20 Then ON
If pH > 8.25 Then OFF
If Time 03:00 to 09:59 Then ON
If Time 10:00 to 20:59 Then OFF

 

[rishma]

Hi @rishma, can you please share your apex code for this? Would like to see how it compares to mine. I am setting my point at 8.25 (based on my dosing regimen at peak light and pH). With my code, I am trying to slow down the drop of pH in the middle of the night to my baseline of 8.0. My dawn light turns on at 6am where I've seen it drop to its lowest point and this is where I kick off some photosynthesis to keep it at 8 and prevent it from dropping further. I do a dose of kalk to restore it back to 8.2 around 9am.

airpump schedule:

Fallback OFF
Set OFF
If pH < 8.20 Then ON
If pH > 8.25 Then OFF
If Time 03:00 to 09:59 Then ON
If Time 10:00 to 20:59 Then OFF

Sorry, because my outdoor air pump is plugged in outside and not near my apex, I am not switching it on/off with apex. I was wishing I could because that would be great to switch based on pH. I am just using a WiFi connected outlet and its app/timer.

 

[Doctorgori]

FWIW these pumps are (allegedly) IPx6 rated

hygger IPX6 Rechargeable Aquarium Pond Air Pump

I have one outside now running some brine shrimp/pod tubs ….
Just posting in case someone implements the OPs idea and needs a outdoor airpump
(Also good for power outages)

 

[bakbay]

FWIW these pumps are (allegedly) IPx6 rated

hygger IPX6 Rechargeable Aquarium Pond Air Pump

I have one outside now running some brine shrimp/pod tubs ….
Just posting in case someone implements the OPs idea and needs a outdoor airpump
(Also good for power outages)

Thanks for sharing - my skimmer is a BK300 and the max air intake is 600gph and the max of the above pump can do 300gph. This won’t get the desired result right? Also, what if the pump is clogged or run out of battery/power? This method will overflow the skimmer, right?

 

[Doctorgori]

Thanks for sharing - my skimmer is a BK300 and the max air intake is 600gph and the max of the above pump can do 300gph. This won’t get the desired result right? Also, what if the pump is clogged or run out of battery/power? This method will overflow the skimmer, right?

I thought the OP simply bypassed the skimmer and aerated the water directly…I will re-read , but I was thinking airstones and sump here…
Also the unit is a plug in and will operate optionally on batt only
I have a 2nd unit for emergency purposes I might now repurpose thanks to this thread

 

[bakbay]

I thought the OP simply bypassed the skimmer and aerated the water directly…I will re-read , but I was thinking airstones and sump here…
Also the unit is a plug in and will operate optionally on batt only
I have a 2nd unit for emergency purposes I might now repurpose thanks to this thread

lol - that makes the two of us. I thought the OP pumped external air into the skimmer’s intake. If we’re just aerating the sump water, it’s super easy for me. My tank is a 450gal and pH has been depressed so looking for alternatives.

 

[rishma]

I currently run a powerful airpump to an airstone in the sump. This is most effective in my case because I can pump much more air this way than what the skimmer could take.

Others might have success just routing outside air to their skimmer.

 

[bakbay]

I currently run a powerful airpump to an airstone in the sump. This is most effective in my case because I can pump much more air this way than what the skimmer could take.

Others might have success just routing outside air to their skimmer.

I don’t know how to calculate the pump needed to aerate 450gal but what @Doctorgori shared above is relatively cheap at 300gph vs the biggest Tunze.

I haven’t tried to route outside air to the skimmer yet since that involved drilling but I can snake a little 1/4” tube around the corner as a quick test.

 

[rishma]

I don’t know how to calculate the pump needed to aerate 450gal but what @Doctorgori shared above is relatively cheap at 300gph vs the biggest Tunze.

I haven’t tried to route outside air to the skimmer yet since that involved drilling but I can snake a little 1/4” tube around the corner as a quick test.

worth a try.

I am pushing nearly 100gph air into a 25 gallon tank. I do not think this is a guideline, just sharing for context. This is what I mean by massive air. More air pushes the tank closer to equilibrium CO2 with outdoor air.

The amount of air needed to achieve this will depend on many things, including contact time, indoor CO2, pH goals, etc.