Quantitative Airstone Test. an end to the hype

Gigaah said:

It kind of looks like no matter what stone you use. Give the margin of error. They are pretty close to the same. Probably because we are bumping up against the "maximum dissolved oxygen concentration" limit I'm assuming?
http://www.dnr.mo.gov/env/esp/wqm/DOSaturationTable.htm

You can "supersaturate" the water beyond those levels but I don't think you can do so by "normal" means such as air stones/agitation.

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Yes, these stones all performed damn near exactly the same. Sure as hell not enough to make a difference in any system. Water temperature, air pump size, and atmospheric pressure are the only things affecting your total dissolved oxygen levels and total airflow/rootzone oxygenation, not bubble size. Though smaller bubble will oxygenate your water slightly faster. But the water shouldn't ever be without aeration anyway, so this makes no difference whatsoever.

mike91sr said:

Yes, these stones all performed damn near exactly the same. Sure as hell not enough to make a difference in any system. Water temperature, air pump size, and atmospheric pressure are the only things affecting your total dissolved oxygen levels and total airflow/rootzone oxygenation, not bubble size. Though smaller bubble will oxygenate your water slightly faster. But the water shouldn't ever be without aeration anyway, so this makes no difference whatsoever.

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You are just so confused, and have no idea what your saying.

Nice picture. Very helpful in proving my point (you have no proof to back up your ridiculous claims) Are you going to do anything besides attack me, like....I dont know.....PROVE IT? You've been asking for it for several pages now, yet all I see from you is your own theories and experiences being touted as substantiated claims with scientific proof to back it....so where is it?

Staying on topic, something neither of you seem to be able to do. Is it because you have no rebuttal to defend yourself against someone who brings proof to an argument? oooh noooo.

http://www.citycollegiate.com/chapter3d.htm
http://learningcenter.unc.edu/services/handouts/study/Guides/Chemistry 102/Factors Affecting Solubility
http://chem.wisc.edu/deptfiles/genchem/sstutorial/Text11/Tx112/tx112.html
http://en.wikipedia.org/wiki/Solubility#Solubility_of_gases
http://www.saskschools.ca/curr_content/chem30_05/4_solutions/solution1_3.htm
http://www.solubilityofthings.com/basics/factors_affecting_solubility.php I know it says molecular size and you're going to try to say it means bubble size, but lets be sensible here. Bubbles of any size still have the same size molecules, unless you learned how to change the composition and structure of oxygen via airstones?

you said it yourself "smaller bubbles oxygenate the water better" that's what we have been saying all along, Check Mate, you should let up on the smoke boy, your short term is gone...

I have to agree with Woodsmaneh bubble size does matter it increases the surfae area which is directly related to gas exchange at the waters surface.But I also agree with you on the temp,pumpsize.I will look for a article I read on this very subject on a Fish Health forum.Gimmie a few I will post a link if anyone is interested.

Uh-oh, gas exhange at the water's surface. That's a big no no in this thread too.

Bubble size(surface area) affects only rate of solution, not solubility. When somebody here can actually prove otherwise, I'll rip that page out of my main chemistry reference text.
Woodsman, I didn't say that. Stop putting words in my mouth. "faster" is not "better" Faster means it gets to max DO faster. Better would mean it gets to a higher ppm, but it doesnt. Keep your shit straight if youre going to falsely try and tell me to do the same

http://edis.ifas.ufl.edu/ss525 Not what I was talking about but a good read on dissolved oxygen.One thing I read is that water has a low D.O it is oxygenated faster than water with a higher D.O,Im not trying to become part of the argument,trying to have a discussion,and possibly learn something.I will still look for the other information.As opposed to post whoring I will edit this info in.Taken from the Koiphen Forums. "When air is in contact with water, oxygen will enter the water from the air until the pressure of the oxygen in the water is equal to the pressure of the oxygen in the air. Oxygen must enter or leave a body of water at the air-water interface, so for the very thin film of water in contact with air the greater the oxygen deficit or oxygen surplus , the faster oxygen will enter or leave the film. Once in equilibrium oxygen tension is the same in air and water and transfer ceases.

There are many physical and biological factors affecting dissolved oxygen concentration in water such as temperature, pressure (depth), salinity, photosynthesis and respiration amongst many.......Photosynthesis produces oxygen and respiration consumes oxygen.

Our "closed water systems" generates enormous amounts of bio loading from plants and fish, which in turn consume large amounts of oxygen through respiration. Which is one of the reasons we always recommend aeration to near saturation in our ponds...."

Theory of relativity. Einstein. It's the same as temperature changes. Two glasses of water, one is 35*, the other is 55*. Both put into room temp at 75*, the 35* water will change temperature faster. It doesn't mean it will get to 75 before the other though, as it has further to go. It also doesn't mean that it will get to 80*(take note woodsman). Once both cups are at 75*, it doesn't matter what kind of cup they're in or what the surface area is, 75* is 75* no matter how you look at it. It's not going to be any different if it took longer to get there, whether it be the extra hour it takes for the water temp in this example, or the extra 1/4 second it takes for oxygen to dissolve in water.

My point about rate of solution vs solubility is relatively the same, that unless you are letting your water become un-oxygenated, there is no need for it to have the ability to oxygenate faster. It doesn't change the chemical properties that limit how much oxygen can be present.

I've put up about 15 links at this point, mostly to scholastic studies with measured evidence as opposed to the "I think my plants grew faster" claims found in most forums. If you read through every single one of them thoroughly (don't), you'll find ZERO mention of surface area(bubble size) in relation to solubility(DO in this case). You will however find tons of talk about its effect of rate of solution. You need to understand the difference between the two to understand why woodsman is incorrect.

Hey Mike why is gas exchange at the waters surface a nono?I didnt read the whole thread the bickering was a turn off and helped me to skip through some.Can you read my edited post and tell me if its true false or partially both?

Good call skipping through lol, you can see where all the bickering has gotten us....

Anyway, I was mostly kidding about it being a no-no. Throwin another dog into the fight, ya know? And despite the fact that gas is in fact exchanged at the surface and is increased by turbulence and greater surface area(of water, not air bubbles), some people have argued that it's the ONLY place it happens, not in this thread. It apparently pissed off legally bad enough that years later he's still upset. It became apparent somewhere in there lol, I'm not going to look for it and its not worth your time to bother.

mike91sr said:

Good call skipping through lol, you can see where all the bickering has gotten us....

Anyway, I was mostly kidding about it being a no-no. Throwin another dog into the fight, ya know? And despite the fact that gas is in fact exchanged at the surface and is increased by turbulence and greater surface area(of water, not air bubbles), some people have argued that it's the ONLY place it happens, not in this thread. It apparently pissed off legally bad enough that years later he's still upset. It became apparent somewhere in there lol, I'm not going to look for it and its not worth your time to bother.

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Cool man thanks for clarifying so my understanding of it is not that flawed.

You know what's funny? You constantly bumping this thread to the top with your nonsense. Whenever I log in all I see is that my latest rep count just says "quantitative airstone" from top to bottom.

Since your the man of all things hydro, I think we should just settle this with some good old fashioned bud porn.

legallyflying said:

You know what's funny? You constantly bumping this thread to the top with your nonsense. Whenever I log in all I see is that my latest rep count just says "quantitative airstone" from top to bottom.

Since your the man of all things hydro, I think we should just settle this with some good old fashioned bud porn.

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Show me yours Ill show you mine?I used to play that game with girls in jr high!

Here we go again lol. Anytime you want me to shut up, just prove me wrong. Until then, just worry about shipping back your top-of-the-line airstones (and your rep count)

^^. I'll translate that... I've only grown a single crop and it is pitiful (most likely because I'm a hard headed tool)
Prove me wrong! Prove it! Why don't you address this question? Cause you can't prove it? Where is the proof?

Impact of bubble and free surface oxygen transfer on diffused
aeration systems

I supose you think these people don't know what they are talking about?

Connie D. DeMoyera, Erica L. Schierholza, John S. Gullivera,*,
Steven C. Wilhelmsb
a St. Anthony Falls Laboratory, Department of Civil Engineering, University of Minnesota, Mississippi River at 3rd Avenue, SE,
Minneapolis, MN 55414, USA
bUS Army Corps of Engineers Research and Development Center, Waterways Experiment Station, 3909 Halls Ferry Road,
Vicksburg, MS 39180, USA
Received 1 November 2001; received in revised form 1 November 2002

6. Conclusions
The standard testing methodologyfor oxygen transfer
in aerated systems oversimplifies the oxygen transfer
process and makes adjustment of measured values to
other depths intangible. This paper more accurately
describes the oxygen mass transfer process and advances
McWhirter and Hutter’s mass transfer model by
considering both oxygen transfer and the transfer of
other gases, primarilynitrogen, into and out of the
bubbles as theyrise to the water surface. Model results
indicate that the surface-transfer coefficient in a 9.25m
tank with an air flow rate of 51–76 scmh is 59–85% of
the bubble-transfer coefficient. The analysis of the gasphase
oxygen composition and liquid-phase equilibrium
concentration shows that the bubble–water concentration
gradient is also of greater magnitude than the air–
water concentration gradient.
Experiments and analysis designed to determine the
relative location of high surface-transfer coefficients
indicate that the large transfer coefficient directlyabove
the bubble plume is related to air discharge, while the
lower transfer coefficient outside of this region is not
related to air discharge.
Surface transfer and bubble–water transfer both
contribute significantlyto the total oxygen transfer in
this type of diffused aeration system. Bubble–water
transfer, however, is the dominant means of oxygen
transfer. These results were obtained numerically and
verified experimentally. The results can be applied to
aerated systems at similar depths or to deeper water
systems where the higher bubble–water concentration
gradient near the submerged diffuser should cause an
even greater dominance of bubble transfer in the
aeration process. Insight into the relative importance
of transfer across the water surface and bubble surface
can be used to design more effective diffused aeration
systems for lakes, reservoirs, and wastewater treatment
facilities at a varietyof water depths.
Acknowledgements
The experiments described and data presented, unless
otherwise noted, were part of research conducted under
authoritygiven bythe US ArmyCorps of Engineers
District—Chicago. Permission was granted bythe Chief
of Engineers to publish this information. The authors
thank Jian Peng and Miki Hondzo for their conceptual
input into this research and their helpfulness in
conducting aeration tests. We also thank Calvin Buie
and Jason Giovannettone for assisting with aeration
experiments during hot Julyday s in Mississippi.
References
[1] Fischer HB, List JE, Koh RCY, Imberger J, Brooks NH.
Mixing in inland and coastal waters. San Diego: Academic
Press, 1979.
[2] Popel HJ, Wagner M. Modeling of oxygen transfer in deep
diffused-aeration tanks and comparison with full-scale
plant data. Water Sci Tech 1994;30(4):71–80.
[3] McWhirter JR, Hutter JC. Improved oxygen mass transfer
modeling for diffused/subsurface aeration systems. AIChE
J 1989;35(9):1527–34.
[4] American Societyof Civil Engineers. Standard for the
measurement of oxygen transfer in clean water. New York,
NY: ASCE, 1992.
[5] Neilson BJ. Reaeration dynamics of reservoir destratification.
AWWA J 1974;66(10):617–20.
[6] Camp TR. Water and its impurities, 2nd ed. New York:
Reinhold Publishing Corp., 1963. p. 33–5.
[7] Holroyd A, Parker HB. Investigations on the dynamics of
aeration. J. Inst. of Sewage Purification 1949;3:292.
[8] Wilhelms SC, Martin SK. Gas transfer in diffused bubble
plumes. In Jenning SM and Bhowmilk NG, Eds.
Hydraulic Engineering: saving a threatened resource-in
search of solutions. ASCE, New York.
[9] Scouller WD, Watson W. Solution of oxygen from air
bubbles. Surveyor 1934;86(2215):15–6.
[10] Higbie R. The rate of absorption of a pure gas into a still
liquid during short periods of exposure. Am Inst Chem
Eng 1935;31:365–89.
[11] Coppock PD, Meiklejohn GT. The behavior of gas
bubbles in relation to mass transfer. Trans Inst Chem
Eng 1951;29:75.
[12] Ippen AT, Campbell LG, Carver CE. The determination
of oxygen absorption in aeration processes. Mass Inst
Technol Hydrodyn Lab Tech Rep 1952;7.
[13] Pasveer A. Oxygenation of water with air bubbles. Sewage
Ind Wastes 1955;27:1130–46.
[14] Calderbank PH, Moo-Young MB. The continuous phase
heat and mass-transfer properties of dispersions. Chem
Eng Sci 1961;16:39–54.

The full report is here

http://144.206.159.178/FT/1092/86893/1471661.pdf

Mike91 I'm not a weekend grower, I take my growing very serious and go to great lengths to make sure what I do is founded in science and reasearch. Knowing a little about something does not make then an expert, you need to look at the big picture and if smaller bubbles work better than I will keep tweeking my systems till I get the biggest plant I can grow. So in an effort to be the best I can I will apply every thing I learn to that end. Big gains are very hard to get but running a ideal grow enviorment and makeing sure every aspect is as good as it can be = 1# plus plants.

Some people are happy just tossing things together or just doing what everyone else does, someone needs to lead and it's guys like leagllyflying, ucundercurrent and me who try to do that, intresting thing is not maney people can help us as were the leading edge of growing in water so we try to advance the cause by shairing. So if you still got your nickers in a knot lets agree to disagree and get back to the work at hand.

Area to Volume Ratio The specific interfacial area available for mass transfer (a, m1) is expressed as the ratio of the bubble surface interfacial area (A, m2) to water volume (V, m3), Small bubbles afford greater surface area and lead to more efficient gas transfer, e.g. 1m3 of bubbles with a 1 cm diameter have 10 times the surface area of 1m3 with a 0.1 cm diameter. Thus bubble size is a feature of diffuser design. So I guess you can saddle up and ride into the sun set never to be seen again, The lesson her folks is just because your persistant in your views does not make them right, I got to build my knowlage base and prove what I was saying, so was worth it.So more rep for me and a big Zero for you and I would question anything you might have to say in the future...... Go read that book of yours but make sure it's right side up.

Well said sir.

Woodsy, I think the excitement level over the new UC system is actually making my clones root out slowly. Somehow they know I can't wait to stick them in the new system.

And of course...my buddy says "hold off dude, I can cuttings of a dank ass c99". And I just got super skunk seeds in, sprouted another round of super skunk, and just ordered some double barrel OG from dank house.

At any rate, I'm going to post pictures of the "space station 2000" tonight over on that other (less douche bag) forum