Flooming vs Air stones
read a few interesting articles & threads recently, and figured I would post the info I found. Some of it is from koi pond websites but the info is based around oxygenating water, which is as critical for hydroponics as it it for living fish.
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Flooming For Aeration and Water Turnover in Koi and Fish Ponds
When it comes to aeration:
Nothing comes close to "flooming" - This requires nothing more than a water-pump which can lay flat on the pond or tank bottom and force water upward to the surface of the vat.
It is not important, or even desirable for the water being "floomed" to break the surface - we DO NOT want a geyser.
All we want is a gentle swell at the surface where the water looks like it's "bulging" over the pump location. You see, oxygen exchange occurs only in contact with atmospheric "air" which is 21% oxygen. Venturis and other bubblers simply create agitation of the water and the bubbles lift the water to the surface for gas exchange.
Even better, a water pump forces large amounts of water to the surface for gas exchange, and it does so "simply" and very quietly. Flooming is ideal in retailers tanks because, unlike air bubbles, flooming causes less surface distortion so the consumer can still see and buy fish.
A water pump lifts more water than an airstone could EVER lift to the surface for gas exchange.
Almost any brand of pump can work. You will find some pumps "stand up" better than others. It can be disastrous if the pump lays over and stops "flooming" the surface.
Also, if the pump DOES "geyser" the surface the risk is increased that the pond or vat could be pumped dry by the pump if it directed water over the edge and onto the ground.
So, a gentle flooming in any tank or vat is superior aeration. And it's as simple as dropping in a submersible pump and aiming it at the heavens.
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Another Reference Posted @ Flooming VS Airstones
Posted by Desertboy AKA TUTU
I have an ORP controller google it for more information it basically tells me how much O2 is in a usable form in the reservoir. Higher== more O2
The lower figure is 4 12" airstones with a 40l/min pump
the higher one flooming only
With flooming and airstones the ORP was within 5 points of the flooming alone (It was lower) which is close enough to be within natural variation.
Reservoir is temperature controlled which will have the greatest effect on ORP.
Conclusion airstones and airpumps aerate the reservoir 20% less than flooming while increasing the pathogens in the reservoir exponentially.
I have a plant on the go with a DWC without airpumps or airstones
flume
flume
airstone
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"Originally Posted by motherlode
but uhhhh - lol - whats flooming?
and how did you come to the conclusion that airstones exponentially increase pathogens?"
RE: Posted by Desertboy AKA TUTU
air is blown through an airstone which acts like a sponge for bacteria since Pythium is airborne over most of the planet it's not hard to become infected. In fact most reservoirs are infected hence the need for temperature control to keep the infection under control.
I was informed by a pro koi carp farm who ditched the airstones years ago.
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Reply Posted by Seamaiden
A lot of people think that airstones aerate via the bubbles traveling through the water column. This is not the truth. Good O2 saturation can be realized if one's using a venturi and creating superfine bubbles, otherwise, the only gas exchanges occur on the surface, and that's what makes "flooming" (not a term I'm familiar with) so effective.
Another way to achieve these high O2 saturation levels is to create riffles in the water flow (think stream flowing over rocks).
Edit: Reading the flooming article and they're mentioning venturis, the author might want to investigate experiments in water treatment that have shown the venturis raise O2 levels significantly. I know *I* was surprised to read it. I don't know that it's not alright to allow more than a little swell, I personally think it's better to create more turbulence. And in another "article" the koi vet has written he uses the word "irregardless!" LMFAO!!! Right after complaining the the pundits don't have degrees.
This is actually my much preferred source of aquatic information generally. I worked with the man, lived with him for a short time (while I was looking for an apartment) and know that his knowledge is above par. The site is often a Googlewhack, even, and many of his fish photos are the only known photos of some species of fish, and are therefore the only photos you'll find on fishbase.org.
Wetwebmedia, Aquarium, Pond, Marine and Freshwater Fish, reef tanks, and Aquatics Information ---> Bob Fenner. Great guy, IMO.
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Reply Posted By click80
We can take the plant-human symbiotic relationship to another level by increasing the amount of oxygen available to the plant's root zone. Increase the plant's root zone oxygen and the plant will reward you by growing faster and being more productive.
On the contrary, if you fail to supply the root zone with oxygen, the plant will fail to grow vigorously and output high yields.
What it means to oxygenate nutrient solution or grow media
Oxygenating your nutrient solution in a hydroponics application or your grow media, including soil and soilless (Perlite, Clay Pebbles, Rockwool) means to combine o2 with H2O for nutrient solution or allowing o2 to flow through porous grow media.
Before we proceed to the specifics of oxygenating soil and soilless culture root system, It's important to understand how o2 combines its self with H2O. Oxygen is a form of gas found in the atmosphere. Dissolving o2 into water is called a mass transfer process. To accomplish mass transfer, there must be two required parameters.
Firstly, there must be a driving force; the difference between the amount of o2 present in the liquid, and the maximum levels of o2 the water can hold. What this means is water has a threshold of o2 concentration is can hold. This is often referred to as solubility. Henry's Law governs the solubility of a gas substance into liquid.
Secondly, there needs to be an interfacial surface area, the point of contact or interaction between the liquid and the gas. Read on to get a better understanding of what this means for your particular cultivation method.
The degree of solubility of o2 in H2O
Atmospheric oxygen is only sparingly soluble in water. In fact, attempting to combine o2 with water can be an energy intensive process. The range of solubility of o2 into H2O is approximately 15 PPM (Parts Per Million) at 0º C to about 7 ppm at 35º C under 1 atmospheric pressure; Pressure caused by the weight of the atmosphere - The mean value of 1 atmospheric pressure indicates sea-level (at sea level the atmospheric pressure is a mean value of 1). This mean value will decreases with increased altitude.
The temperature of water determines how much oxygen it can hold. Warm water will hold less oxygen than cold. Because of the low solubility rate of o2 into H2O, there is very little driving force to facilitate mass transfer. In order to accomplish any mass transfer on a reasonable time frame, energy must be generated to create an interfacial surface area.
Oxygenating hydroponics nutrient solution
Hydroponics has come a long way since its conception many, many years ago. Commercial hydroponics systems available today typically come with the equipment and technology necessary to facilitate oxygenation of your nutrient solution.
This equipment and technology usually includes a pump to transport oxygen from the atmosphere into the reservoir tank to the air stone which diffuses the oxygen into the nutrient solution. The air stone will diffuse tiny oxygen bubbles measuring a mere 1-2 mm in diameter, which create the interfacial surface area required for mass transfer.
Although the diffused bubbles are extremely small in size, the majority of the released oxygen (90-95%) created by this method will escape from the nutrient solution back into the atmosphere and is thought to be wasted energy -- unless the plants root are partially airborne. If the roots are partially airborne like in NFT systems, for example, they will benefit from the escaping oxygen.
The alternative to using air stones and a pump
Adding 1 pint of hydrogen peroxide to 1 gallon of water can super-oxygenate your nutrient solution. Hydrogen peroxide is two hydrogen atoms with one oxygen atom. For this reason, Hydrogen peroxide is know as H2O2. Adding H2O2 to H2O will release the extra atom which attaches itself to bacteria and other impurities that may be present, thereby disinfecting the solution. Combine the hydrogen to the water, shake vigorously for 5-10 seconds and leave over night. The next day, you will have a clean water-hydrogen peroxide solution. Add this solution to your reservoir and the extra oxygen atom will attach itself to the roots, aiding in nutrient uptake.
Oxygenating grow media
Oxygenating a grow media is not as complex as saturating liquid with gas. To facilitate aeration of your grow media, the medium needs to be porous; Admitting the passing of gas (eww).
In hydroponics application, the escaping oxygen from the nutrient solution will aid in the aeration of the grow media
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Originally Posted @
Posted by Dr-Solo
it is complete and utter nonsense. the fine air bubbles put into the water by good
airstones lifts the entire water column from below, it blows toxic gases out while it
vastly increases oxygenation of the water. looks like somebody wasnt paying
attention in physics classes.
and, I might add, take a look at how many watts that water pump is sucking up and
produces a vastly inferior aeration.
Now if that pump is for the filter and that runs over rocks that break the stream up
and puts it out over a nice vast surface, that is economical aeration.
Yes, in winter I use my pump in one of my bucket filters to gently roll the surface
as well... but I have my air pump going all winter for aeration. And there are a lot
of people have had to learn the hard way that in cold climates proper aeration is
MORE important that pumps. The die offs dont occur in winter, it occurs in spring
when all the bacteria on the bottom start getting active and using up the oxygen
crunching up the settled organics at the same time the fish metabolism starts
increasing oxygen demand.
Giving it a new name doesnt make it any truer.
Ingrid
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Reply by Sean Dinh
I have to disagree here. Fine air bubbles can't really blows any gases out of the water.
Gas exchange need to happen at water/air interface. What fine air bubbles really doing
for gas exchange is to move water from the bottom to the surface. In this pump mode, fine
air bubbles has little efficiency without the aid of ducting.
Any pump that move water from bottom to the water/air interface could be considered
'vastly increasing' oxygenation, in a sense that oxygenation rate is higher for
relatively oxygen poor water from the bottom as compared to water from the top. I won't
go as far as claiming airstone 'vastly increases' oxygenation. I reserve that for cooling
tower/TT.
The main reason that airstones are so popular in aerating large ponds, lakes, and sewage
treatment plants is that it's very low maintenance water pump. The only thing to maintain
is to clean the air filter. It's considered the most reliable way to aerate water. There
is nothing more besides that feature.
As for flooming, it does work. If it's good enough for sewage treatment plants, it's good
enough for our ponds.
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Reply Posted by how
Hi,
Fine bubbles or any bubbles are, in fact, a water/air interface.
Supersaturated gasses can escape using bubbles and oxygen is added to the
water. I went back to my notes and although the pump method (flooming) does
oxygenate, it does so by spreading the bottom water over 'hundreds of square
feet of surface' as it 'falls downhill'. Not everyone has hundreds of square
feet of surface or wants to run another pump. The bubble method works much
better but better yet when powered by a blower. This gives the best of both,
a large upwelling at the surface which consists of thousands of little
bubbles.
L8R -_- how
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Reply by dr-solo
of course in a natural lake oxygen exchange occurs at the surface, which is why there
are the OLD recommendations for X amount of surface per inch of fish.
then came aeration and it wasnt necessary to calculate surface area any more.
Yes, of course oxygen change occurs across a bubble and much much more efficiently
since exchange occurs as a function of the entire surface of the bubble (the smaller
the bubble the higher the surface to volume ratio). at the same time when the
bubbles break the surface and are blown into the air now there is exchange going on
the inside and the outside of that air bubble. even more efficient. it is a myth
that it doesnt happen.
the water at the bottom of the pond in summer is going to be cooler than the water at
the top if there is no circulation and cooler water holds more oxygen than warm
water. the water at the top is heating up and losing oxygen. there is no reason the
water on the bottom is depleted of oxygen unless there is a thick layer of rotting
organics on the bottom. correct, airstones are easy to maintain AND most efficient at aerating water. more so than "fountains" altho fountains are lovely to look at.
In sewage plants the last thing anybody wants is to aerate the water in such a way
that blows bubbles up into the air. this would put potentially pathogenic bacteria,
viruses and parasites right up into the air where it would get blown all over the
city. but sewage is broken down by both aerobic and anaerobic bacteria so pumping
it up without actual aeration may be the reason.
INgrid
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Reply by Tom L. La Bron
How,
The technique with air is right and wrong in Ingrid's
statement. The larger the bubble produced by an air
diffuser moves more water to the surface lifting large
quantities of water off the bottom of the pond
preventing layering circulating the water, but the
finer the bubble you have in your air diffuser the more
air/oxygen exchange there is within the water as the
bubbles move to the surface. If you use large bubble
air diffuser you get the same effect as having a pump
at the bottom of the pond. In the winter, through, it
is better to use an aerator with fine bubbles because
you get the air/oxygen exchange with less disturbance
of the water column bringing less the water from the
bottom to the top to be cooled off as the very small
bubbles float leisurely to the surface.
In addition, for the pump to really be affective in
this technique the stream of water needs to break the
water surface tension slightly, which is where air
diffusers are superior because of the busting of the
bubbles as they break the surface.
Personally, I think that the flooming term is silly.
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Originally Posted @
Posted by neville
I have been hoping for this thread for a long time.
In my opinion as you very well know "Flooming" is the more effective method by a long shot. Its ability to displace water that is oxygen depleted to the surface for regeneration is far superior to that of an air stone. I did a little test the other day. Took some strong PP and pulled it into a syringe and with a tube attached injected it next to an air stone, well none of it was moved to the surface.
It is rather logical that a bubble cannot move water unless it is contained in a tube to create some pressure. It only disturbs the surface water that is already well oxygenated. Therefore if you want to use air fine then place the airs tone inside a tube that has slots at the bottom and I am sure it will work. (not tested). Here I would actually like to do a test using a flexible tube that wont injure your fish, some kind of sock.
Then off course there is the noise factor as well, Your fish take a long time to get used to an air stone.
One can however argue that you are drawing water from the bottom drains and it is oxygenated due to circulation. Well yes this is partly true if your turnover rate is very high, in which case you don't need any extra aeration anyway.
Lastly, another relevant stone in the bush, I will take a bet that with flooming your water will be brighter and fish skin quality will improve.
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Reply by Pieter
When I started researching flooming versus airstones a while ago, the first question that I asked myself is why is a venturi a better option to create better movement in the water than a normal mid-water return? I found the answer very quickly.
If a jet of water is injected into a water body, it does not create such a "pushing force" as when a mixture of air and water are injected into the same water body
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Reply by neville
This statement I have to agree with as my own compressed air sand filter assist cleaning kit works on this principle. Air mixed into a stream certainly creates more turbulence. But we are not chasing turbulence here, what we want is to oxygenate the water that is sitting at the bottom of your pond.
But Pieter we want to bring the oxygen depleted water to the surface, and an air bubble does not do it effectively. IMO.
Pieter flooming actually makes more turbulence at the surface, it is just not as visible as air bubbles.
Have you ever stood next to a river and watched what happens at the surface. That is natural flooming at its best. It is not some rocks at the bottom creating those swirls, it is natures way.
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Originally Posted by annon51
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