Micro Scrubbing Bubbles.

[Lasse]

There is some questions that arise in my head (and stomach )

1. There is a lot of links and talks about nanobubbles (bubbles less than 200 nm). Of own experiences – I know that I can´t see single objects less than 200 micrometre in water. The reason why I can see mikrobubbles is the mist. The question is - can we see nanobubbles in an aquarium? How do we know that we with help of a wooden air stone and an impeller pump can generate nanobubbles? The equipment I have seen for generating nanobubbles works with rather high pressure pumps (around 3 bars) (link at post 485) There has been claims that the technique with wooden air stones generate 1-5% nanobubbles. How do we know that?

2. There is claims that the nanobubbles rise the export of organic matter from the DT. The reason to this should be that the nanobubbles on its way up to the surface pick up organic matter because they are negative charged. What I understand of the links posted about nanobubbles they could get this negative charges – but on the other hand – on of the properties of nanobubbles is that they do not rise to the surface – they just stay still in the water column for days. I can buy that microbubbles are able to lift things up to the surface for further transport to the skimmer through the surface overflow – but I have difficult to understand the nanobubbles part of this.

3. Bubbles that stays in the aquarium for days (nanobubbles) – how can they transport away dinos and cyano? If nanobubbles can kill these plagues – there must be another mechanism responsible for the killing.

4. Maybe I misunderstand everything – but please explain for why links about nanobubbles is so common in this thread. It is hard for me to accept that is possible to produce nanobubbles with help of a wooden air stone and an impeller pump.



As you understand – English is not my prime language and a big difference between Swedish and English is the sentence structure. Please – do not get offended by my broken English – try to understand what I´m trying to say instead of read what I write


Sincerely Lasse

 

[The Macro Guy]

There is some questions that arise in my head (and stomach )

1. There is a lot of links and talks about nanobubbles (bubbles less than 200 nm). Of own experiences – I know that I can´t see single objects less than 200 micrometre in water. The reason why I can see mikrobubbles is the mist. The question is - can we see nanobubbles in an aquarium? How do we know that we with help of a wooden air stone and an impeller pump can generate nanobubbles? The equipment I have seen for generating nanobubbles works with rather high pressure pumps (around 3 bars) (link at post 485) There has been claims that the technique with wooden air stones generate 1-5% nanobubbles. How do we know that?

2. There is claims that the nanobubbles rise the export of organic matter from the DT. The reason to this should be that the nanobubbles on its way up to the surface pick up organic matter because they are negative charged. What I understand of the links posted about nanobubbles they could get this negative charges – but on the other hand – on of the properties of nanobubbles is that they do not rise to the surface – they just stay still in the water column for days. I can buy that microbubbles are able to lift things up to the surface for further transport to the skimmer through the surface overflow – but I have difficult to understand the nanobubbles part of this.

3. Bubbles that stays in the aquarium for days (nanobubbles) – how can they transport away dinos and cyano? If nanobubbles can kill these plagues – there must be another mechanism responsible for the killing.

4. Maybe I misunderstand everything – but please explain for why links about nanobubbles is so common in this thread. It is hard for me to accept that is possible to produce nanobubbles with help of a wooden air stone and an impeller pump.



As you understand – English is not my prime language and a big difference between Swedish and English is the sentence structure. Please – do not get offended by my broken English – try to understand what I´m trying to say instead of read what I write


Sincerely Lasse

The nano bubbles still bind particles, they may not float to the surface, but at some point it does go into your sump, and then into your skimmer, as does 80-90% of your tanks water. So you micro bubbles busting up and lifting the large stuff and nano bubbles doing the other little odds and ends of clean up. My overflow chamber has an inner wall with a holes at the bottom, so water rises up and over from all zones of my tank.

 

[cb684]

1. There is a lot of links and talks about nanobubbles (bubbles less than 200 nm). Of own experiences – I know that I can´t see single objects less than 200 micrometre in water. The reason why I can see mikrobubbles is the mist. The question is - can we see nanobubbles in an aquarium? How do we know that we with help of a wooden air stone and an impeller pump can generate nanobubbles? The equipment I have seen for generating nanobubbles works with rather high pressure pumps (around 3 bars) (link at post 485) There has been claims that the technique with wooden air stones generate 1-5% nanobubbles. How do we know that?

I would expect to see turbidity even after a while after the bubbles were generated...

2. There is claims that the nanobubbles rise the export of organic matter from the DT. The reason to this should be that the nanobubbles on its way up to the surface pick up organic matter because they are negative charged. What I understand of the links posted about nanobubbles they could get this negative charges – but on the other hand – on of the properties of nanobubbles is that they do not rise to the surface – they just stay still in the water column for days. I can buy that microbubbles are able to lift things up to the surface for further transport to the skimmer through the surface overflow – but I have difficult to understand the nanobubbles part of this.

I had the same question. I am guessing (guessing) that as the water passes through the sump these bubbles will also go (as would the diluted organics) and then combine with bubbles in the skimmer increasing the skimmate (see Randy answer # 508)
Edited: I was also worried that I would not be able to remove them from the tank.

3. Bubbles that stays in the aquarium for days (nanobubbles) – how can they transport away dinos and cyano? If nanobubbles can kill these plagues – there must be another mechanism responsible for the killing.

Again, my guess is that, if it works, it is not because it is floating, but is because is dislodging the particles and bringing to the water column so it will pass through the sump.

4. Maybe I misunderstand everything – but please explain for why links about nanobubbles is so common in this thread. It is hard for me to accept that is possible to produce nanobubbles with help of a wooden air stone and an impeller pump.

I guess the question is how much nano bubbles is necessary to see any effect... I do not know.
Edited: It also makes me wonder how much nano bubbles the skimmers are creating and if this is part of their function at all. I mean, even if they only form 1% or 0.1% that would amount a lot in a 24 hours/day with something so stable. Well, now that I am reading what I wrote it sounds like it is unlikely that they produce and release them in the water column...

 

[Chibils]

@Lasse - I think you understood everything fine - or I misunderstood it as we are in the same place in our understanding. I think all your questions are on point.

What is the difference in effect between "nano-bubbles" of 20nm or less, and "micro-bubbles" of 30um or so? Is it simply a function of surface area to volume favoring nano-bubbles for gas exchange and organic binding? Or is this speculation?

How do we know these nano-bubbles are being generated if they are so small that they cannot be seen in the water column? As Lasse says, where does the claim of 1-5% production of nano-bubbles on limewood airstones come from?

 

[The Macro Guy]

@Lasse - I think you understood everything fine - or I misunderstood it as we are in the same place in our understanding. I think all your questions are on point.

What is the difference in effect between "nano-bubbles" of 20nm or less, and "micro-bubbles" of 30um or so? Is it simply a function of surface area to volume favoring nano-bubbles for gas exchange and organic binding? Or is this speculation?

How do we know these nano-bubbles are being generated if they are so small that they cannot be seen in the water column? As Lasse says, where does the claim of 1-5% production of nano-bubbles on limewood airstones come from?

It's evident from the mist or fog that's generated in the water column when you do this that there are bubbles of all sizes including micro and nano. Does the % really make a difference though? Will people not do this because it only generates 3% nano bubbles compared to 15% from whatever other device?

I don't see the argument now of why this went from there was no proof that microscrubbing worked, to if the bubble sizes are right or not for it to work in theory.

 

[cb684]

I don't see the argument now of why this went from there was no proof that microscrubbing worked, to if the bubble sizes are right or not for it to work in theory.

I agree... I think the only reason the discussion is at this level is because they are cool and there is a lot of benefits in other fields. So, we wanted to play with them.
But all the questions are very fair so far...

 

[Lasse]

http://www1.lsbu.ac.uk/water/nanobubble.html

Sincerely Lasse

 

[Chibils]

It's evident from the mist or fog that's generated in the water column when you do this that there are bubbles of all sizes including micro and nano. Does the % really make a difference though? Will people not do this because it only generates 3% nano bubbles compared to 15% from whatever other device?

I don't see the argument now of why this went from there was no proof that microscrubbing worked, to if the bubble sizes are right or not for it to work in theory.

I did not mean to insinuate anything. I think the conversation has shifted because the arguments for and against have been made. There's nothing left to do but wait for long-term results, either success, failure, or no discernible change. I'm asking because if this method works then we should be attempting to improve it. We can do this by quantifying what is working and what isn't.

We have explained how this works (presumably - I am not a chemist like @Randy Holmes-Farley), so my questions are directed at the specifics. I so far do not understand nano-bubbles fully. They are very small, <=20nm. It's being speculated that the nano-bubbles are doing the work of oxygen regulation and organic waste binding, correct? We want the bubbles as small as possible? E.g. if we had an air pump and diffuser that could produce the same quantity of air in the form of 100% nano-bubbles, would that be preferable to what people in this thread are using (estimated at 1-5% nano-bubbles)? Or is a mixture of micro- and nano-bubbles important to the process people are having results with? What is it about bubbles in size below 20nm compared to bubbles in the 20-30um range that make them better?

We cannot tell how this will work in the long term. So far all the posts I have read have been either neutral or positive. But people are very excited about this method, so no one wants to sit back and wait 3 to 5 years to see how it turns out. I therefore see two goals ahead if this is to be taken to a broader audience; one serves newcomers, the other those who wish to advance this practice:
1. Clarify the mission of nano-scrubbing for those who are interested in trying it -- what it can achieve:

1a. oxygen regulation
1b. pH stabilization
1c. foam fractionation ("turning the tank into a skimmer") by binding organic waste and likely clearing the water column
1d. speculative - possible long-term growth benefits for corals, reduction in nuisance algaes, bacteria, and dinoflagellates.​

2. Clarify the process of nano-scrubbing for those who are using it, so that it may be better understood and improved -- how far can we take this:

2a. what is the relation of micro-bubbles and nano-bubbles?
2b. is one more effective than the other at producing the above positive results?
2c. what is the ideal density of bubbling? a light fog in the tank, or a milky white jacuzzi? Can the bubbles be "overdosed"?
2d. what is working (in terms of products and practices) and what isn't? Are venturi needlewheel pumps producing better bubbles than a $10 aquarium air pump? How about air compressors? Wood or ceramic air stones?
2e. how do you size this to your tank? You don't put an 800G skimmer on a 120G tank or you'll never get a good foam head. Likewise, a TUNZE 9001 will be working so much overtime it'll take a week to process 1X the tank's volume. There needs to be some kind of guideline for figuring out how to size air pumps and stones to a tank.
​

I would also be very curious to see PAR readings taken the day before nano-scrubbing begins and a few weeks after. It is my understanding that the nano-bubbles can stay in suspension for hours or days, meaning that even during lights-on you likely still have some nano-bubbles in your display. Light scattering/blockage by the water column is also one of the biggest reducing factors in PAR in reef tanks, meaning lots of "junk" suspended in the water can significantly reduce PAR readings at depth. It would be interesting to see if the clearing of the water by nano-bubbles offsets the light diffusion they create. That would mean nano-scrubbing would either be a net neutral effect or a net positive effect on PAR levels.

I am very sorry for the long post, but now that I'm home at my computer I wanted to post all my thoughts and questions.

 

[Randy Holmes-Farley]

That somewhat explains the link between the scrubbing and the dinos and cyano since the negative charged bubbles grab the bacteria no? Or did I miss interpret the diagram.

From another post yesterday:

I'd be very reluctant to claim the reason for bacteria adhering to the surface is a charge based effect. Most bacteria have a net negative charge. Some in seawater may have a net positive charge, but I wouldn't be convinced the small effect of hydroxide vs H+ at the bubble interface that gives the negative charge would remain intact in the presence of a whole bacteria arriving at the interface and displacing other stuff from the interface.

In short, the bacteria stick out of the surface with organic matter exposed to the air, not just adhering to it but still in the water. This is how organics are skimmed, for example.

see this article:
http://aem.asm.org/content/62/7/2593.full.pdf

Bacterial Enrichment at the Gas-Water Interface of a Laboratory Apparatus
last sentence of the abstract:
"The strong effect of d and the lack of effect of I and p support the hypothesis that hydrophobic interaction dominates bacterial adsorption to the GWI."
(GWI = gas water interface)

 

[The Macro Guy]

I did not mean to insinuate anything. I think the conversation has shifted because the arguments for and against have been made. There's nothing left to do but wait for long-term results, either success, failure, or no discernible change. I'm asking because if this method works then we should be attempting to improve it. We can do this by quantifying what is working and what isn't.

We have explained how this works (presumably - I am not a chemist like @Randy Holmes-Farley), so my questions are directed at the specifics. I so far do not understand nano-bubbles fully. They are very small, <=20nm. It's being speculated that the nano-bubbles are doing the work of oxygen regulation and organic waste binding, correct? We want the bubbles as small as possible? E.g. if we had an air pump and diffuser that could produce the same quantity of air in the form of 100% nano-bubbles, would that be preferable to what people in this thread are using (estimated at 1-5% nano-bubbles)? Or is a mixture of micro- and nano-bubbles important to the process people are having results with? What is it about bubbles in size below 20nm compared to bubbles in the 20-30um range that make them better?

We cannot tell how this will work in the long term. So far all the posts I have read have been either neutral or positive. But people are very excited about this method, so no one wants to sit back and wait 3 to 5 years to see how it turns out. I therefore see two goals ahead if this is to be taken to a broader audience; one serves newcomers, the other those who wish to advance this practice:
1. Clarify the mission of nano-scrubbing for those who are interested in trying it -- what it can achieve:

1a. oxygen regulation
1b. pH stabilization
1c. foam fractionation ("turning the tank into a skimmer") by binding organic waste and likely clearing the water column
1d. speculative - possible long-term growth benefits for corals, reduction in nuisance algaes, bacteria, and dinoflagellates.​

2. Clarify the process of nano-scrubbing for those who are using it, so that it may be better understood and improved -- how far can we take this:

2a. what is the relation of micro-bubbles and nano-bubbles?
2b. is one more effective than the other at producing the above positive results?
2c. what is the ideal density of bubbling? a light fog in the tank, or a milky white jacuzzi? Can the bubbles be "overdosed"?
2d. what is working (in terms of products and practices) and what isn't? Are venturi needlewheel pumps producing better bubbles than a $10 aquarium air pump? How about air compressors? Wood or ceramic air stones?
2e. how do you size this to your tank? You don't put an 800G skimmer on a 120G tank or you'll never get a good foam head. Likewise, a TUNZE 9001 will be working so much overtime it'll take a week to process 1X the tank's volume. There needs to be some kind of guideline for figuring out how to size air pumps and stones to a tank.
​

I would also be very curious to see PAR readings taken the day before nano-scrubbing begins and a few weeks after. It is my understanding that the nano-bubbles can stay in suspension for hours or days, meaning that even during lights-on you likely still have some nano-bubbles in your display. Light scattering/blockage by the water column is also one of the biggest reducing factors in PAR in reef tanks, meaning lots of "junk" suspended in the water can significantly reduce PAR readings at depth. It would be interesting to see if the clearing of the water by nano-bubbles offsets the light diffusion they create. That would mean nano-scrubbing would either be a net neutral effect or a net positive effect on PAR levels.

I am very sorry for the long post, but now that I'm home at my computer I wanted to post all my thoughts and questions.

I don't think there is a sure fire way to measure gallons to this method, there are too many other factors like flow, even your rock work, skimmer setup, sump setup, type of air pump, how long of piping on your return, etc. Which is why I mentioned awhile back in the thread not to over complicate it. Complication scares people away.

For me it was easier to just say put the wooden airstone on a valve and intensify or lower the bubble output based off what you see in your display, it shouldnt be so much micro bubbling that you can't see your corals at all, or enough to cause a fog that doesn't let you see half way into your tank. Once it's on a normal 6-8 hour a night schedule you will see less and less bubbles as the days or weeks pass. At that point you can cut your microscrubbing time in half, then just leave it. Replace the wood airstone when you notice the bubbles are getting bigger. (5-6 month)

Someone mentioned they run enough bubbling that they cant see into the tank and they've had no issues. For me personally I'm a little worried to try that much, but I know that the amount I'm using now works for my 210G system.

With an wood airstone let's just say yeah there is a 10-20% nano bubble creation, it's obvious there is some from the fine fog created. Now what effect would 100% nano bubbles have? It goes back to that saying, too much of a good thing isn't always so good. There has to be a balance.

If someone wants to point us in the right direction for a cheap high pressure pump and nozzle or a nano bubble producer, I may try it for the sake of trying and report back in a month, I would definitely run this at on a much shorter time frame though.

I know I seem a little blunt about people just trying microscrubbing, but it's for good reasons. I've seen many people spend hundreds of dollars and hours or just straight up quit reefing all together because of things related to what micro-scrubbing would have definitely helped in alleviating. I wish I would've known then what I know and have seen now.

 

[The Macro Guy]

From another post yesterday:

I'd be very reluctant to claim the reason for bacteria adhering to the surface is a charge based effect.

see this article:
http://aem.asm.org/content/62/7/2593.full.pdf

Bacterial Enrichment at the Gas-Water Interface of a Laboratory Apparatus
last sentence of the abstract:
"The strong effect of d and the lack of effect of I and p support the hypothesis that hydrophobic interaction dominates bacterial adsorption to the GWI."
(GWI = gas water interface)

The bacteria is a physical entity, even if the negative charge doesn't relate to grabbing the bacteria, at some point in time the water column bacteria collides with the nano or micro bubble and gets stuck no? Or they go through the process of creating a biofilm and get stuck to the bubbles anyways?

 

[blacktippr]

I feed my fish a steady diet of ginger and shark fin and I've never had an ich outbreak!

Shark fin?

 

[Chibils]

I don't think there is a sure fire way to measure gallons to this method, there are too many other factors like flow, even your rock work, skimmer setup, sump setup, type of air pump, how long of piping on your return, etc. Which is why I mentioned awhile back in the thread not to over complicate it. Complication scares people away.

For me it was easier to just say put the wooden airstone on a valve and intensify or lower the bubble output based off what you see in your display, it shouldnt be so much micro bubbling that you can't see your corals at all, or enough to cause a fog that doesn't let you see half way into your tank. Once it's on a normal 6-8 hour a night schedule you will see less and less bubbles as the days or weeks pass. At that point you can cut your microscrubbing time in half, then just leave it. Replace the wood airstone when you notice the bubbles are getting bigger. (5-6 month)

Someone mentioned they run enough bubbling that they cant see into the tank and they've had no issues. For me personally I'm a little worried to try that much, but I know that the amount I'm using now works for my 210G system.

With an wood airstone let's just say yeah there is a 10-20% nano bubble creation, it's obvious there is some from the fine fog created. Now what effect would 100% nano bubbles have? It goes back to that saying, too much of a good thing isn't always so good. There has to be a balance.

If someone wants to point us in the right direction for a cheap high pressure pump and nozzle or a nano bubble producer, I may try it for the sake of trying and report back in a month, I would definitely run this at on a much shorter time frame though.

I know I seem a little blunt about people just trying microscrubbing, but it's for good reasons. I've seen many people spend hundreds of dollars and hours or just straight up quit reefing all together because of things related to what micro-scrubbing would have definitely helped in alleviating. I wish I would've known then what I know and have seen now.

My apologies. I did not mean to complicate things. I was thinking with that "formula" that we might be able to say to people who wanted to try this, with more testing, "a 100LPH air pump like a Tetra insert model would be a good size for your 75G tank".

And you implied that it's good to have some micro bubbles, and not only nano bubbles? I know you're not a scientist but you are suggesting that we want micro bubbles as well as nano bubbles. Did I misinterpret that?

 

[The Macro Guy]

My apologies. I did not mean to complicate things. I was thinking with that "formula" that we might be able to say to people who wanted to try this, with more testing, "a 100LPH air pump like a Tetra insert model would be a good size for your 75G tank".

And you implied that it's good to have some micro bubbles, and not only nano bubbles? I know you're not a scientist but you are suggesting that we want micro bubbles as well as nano bubbles. Did I misinterpret that?

Ah I see, Nah I'd say just grab whatever air pump is in your old fish drawers and setup, I had 4 for whatever reason lol. As long as it isn't a high pressure pump, might burst or splinter your wooden airstone, with the control valve it doesn't really matter too much, and I don't think it's possible to have too weak of an air pump in our tank setups.

For the micro/nano discussion, I don't believe 1 is possible without the other. Even from the airstone itself, I see different sized bubbles including the fog & mist. Then getting processed through the return pump I believe is producing an even finer % of bubbles.

There is also a choke point in your return nozzles which may effect microscrubbing, I normally use 1/2 circle returns, and I tried a reducer down to 3/4 with an even smaller nozzle hole (to push the bubbles deeper into the tank), the bubbles would only trickle out and then build up and 1 big bubble every few seconds, I was losing micro bubbles when using a reducer.

 

[Chibils]

Thanks @The Macro Guy, this is the info I wanted!

 

[Squamosa]

The bacteria is a physical entity, even if the negative charge doesn't relate to grabbing the bacteria, at some point in time the water column bacteria collides with the nano or micro bubble and gets stuck no? Or they go through the process of creating a biofilm and get stuck to the bubbles anyways?

From reading the literature we know that true nanobubbles (<200nm in size) exhibit an ionic shell that is negatively charged, thereby attracting positively charged ions.
These bubbles become very stable and have a high oxidising/sterilizing capacity when these bubbles eventually collapse in the water column.

I quote from the interview by Dr Masoyoshi Takahashi in 2010 in the Nanotech Japan bulletin.
http://mnbtechthailand.com/file/Introduction/Nanotech Japan bullettin.docx

'The rapid increase in the pressure of bubbles during shrinkage is due to adiabatic compression when the rate of increase is high, which also causes the temperature in the bubbles to rapidly increase. This results in the formation of a region with a temperature of several thousand centigrade under a pressure of several thousand atm at the point where the bubble disappears. This ultimate reaction site (hot spot) is limited to a very small region but the reaction is sufficiently strong to decompose internal gas molecules, generating free radicals such as •OH with strong oxidizing power. Free radicals are also generated in the course of natural collapse of microbubbles by hydrodynamic engineering, although its mechanism is different from that of the collapse from ultrasonic engineering'

Masatoshi Takahashi, 2005. “The Potential of Microbubbles in Aqueous Solutions –-Electrical property of the gas-water interface”， J.Phys.Chem. B，109- ，pp.21858 -21864，
Masatoshi Takahashi， Kaneo Chiba and Pan Li, 2007.“Formation of Hydroxyl Radicals by Collapsing Ozone Microbubbles under Strongly Acidic Conditions”.J.Phys.Chem. B，111-39，pp.11443-11446
Masatoshi Takahashi， Kaneo Chiba and Pan Li, 2007. “Free-Radical Generation from Collapsing Microbubbles in the Absence of a Dynamic Stimulus”，J.Phys.Chem.B，111-6， pp.1343 -1347，

 

[Lasse]

1 question more

If we can produce nanobubbles with a cheap wooden air stone - why does we not produce any nanobubbles in our skimmers? The nanobubbles should - if they were produced in the skimmer - been transpoeted out to the DT because they can stand in the water for weeks.

I´m not saying that the bubble scrubbing method not work - because I have not try the method but i doubt that there is nanobubbles involved in the action.

Sincerely Lasse

 

[Randy Holmes-Farley]

From reading the literature we know that true nanobubbles (<200nm in size) exhibit an ionic shell that is negatively charged, thereby attracting positively charged ions.
These bubbles become very stable and have a high oxidising/sterilizing capacity when these bubbles eventually collapse in the water column.

I quote from the interview by Dr Masoyoshi Takahashi in 2010 in the Nanotech Japan bulletin.
http://mnbtechthailand.com/file/Introduction/Nanotech Japan bullettin.docx

'The rapid increase in the pressure of bubbles during shrinkage is due to adiabatic compression when the rate of increase is high, which also causes the temperature in the bubbles to rapidly increase. This results in the formation of a region with a temperature of several thousand centigrade under a pressure of several thousand atm at the point where the bubble disappears. This ultimate reaction site (hot spot) is limited to a very small region but the reaction is sufficiently strong to decompose internal gas molecules, generating free radicals such as •OH with strong oxidizing power. Free radicals are also generated in the course of natural collapse of microbubbles by hydrodynamic engineering, although its mechanism is different from that of the collapse from ultrasonic engineering'

Masatoshi Takahashi, 2005. “The Potential of Microbubbles in Aqueous Solutions –-Electrical property of the gas-water interface”， J.Phys.Chem. B，109- ，pp.21858 -21864，
Masatoshi Takahashi， Kaneo Chiba and Pan Li, 2007.“Formation of Hydroxyl Radicals by Collapsing Ozone Microbubbles under Strongly Acidic Conditions”.J.Phys.Chem. B，111-39，pp.11443-11446
Masatoshi Takahashi， Kaneo Chiba and Pan Li, 2007. “Free-Radical Generation from Collapsing Microbubbles in the Absence of a Dynamic Stimulus”，J.Phys.Chem.B，111-6， pp.1343 -1347，

I'm not convinced that all of these papers discussing things like ozone microbubbles or bubbles created by ultasound cavitation relate that much to what we are doing, but the last one does suggest that ordinary microbubbles create radicals when collapsing. If enough free radicals are generated, the effect may be readily observed by ORP, and there is the potential concern for ORP getting too high with too much bubbling. One generally doesn't want to expose living tissue to free radicals.

OTOH, if the effects in reef tanks come just from aeration and organic removal, the ORP may rise but should not get too high.

 

[Squamosa]

the effects in reef tanks come just from aeration and organic removal, the ORP may rise but should not get too high.

This could very well be the case here!

I don't have the ORP data, but I believe @cruz has some of that data or knows someone who has measured it over time, perhaps he's done his own measurements?

 

[d2mini]

As you understand – English is not my prime language and a big difference between Swedish and English is the sentence structure. Please – do not get offended by my broken English – try to understand what I´m trying to say instead of read what I write


Sincerely Lasse

Lasse, for what it's worth, you speak (or write) better English than most of us on this forum.