How can I get more Oxygen in my water?

the reason "bubbles" don't oxygenate the water is because they don't have sufficient 'residence time' and the phenomenon known as 'surface tension'. in other words, the bubbles emmitted by bubblers and such make it to the surface long before oxygen can be exchanged at the bubble/water interface, and the surface tension of the bubble holds the oxygen within the sphere. oxygen diffuses and is exchanged at the surface simply because the residence time is infinite.

the solubility of oxygen in water is roughly proportional to the partial pressure of oxygen in the air. oxygen gets into water by diffusion from the surrounding air, by aeration (rapid movement), and as a waste product of photosynthesis. as temperature increases, the concentration at 100% saturation decreases. the salinity of the water also affect this saturation value but to a lesser extent. the dissolved oxygen concentration for 100% air saturated water at sea level is 8.6 mg O2/L at 25°C (77°F).

at colder temperatures, water can hold more oxygen and water under pressure can hold more oxygen but for the purposes of aquarium discussion, pressure is not a factor and colder temperatures are meaningful only for goldfish.
 
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You calm down Mr.! =D
thats Mrs. D!
just tired of some who don't care about helping, just telling people that they are right...:mad2:
 
I always understood that you oxygenate by agitating the surface of the water so e.g. an airstone doesn't work because of the bubbles in the water, but because the bubbling causes ripples.

So you can add an airstone, or adjust your filter flow up if that's practical for your set-up, or add a spray bar.

I'm very new - someone else on here will give you great definitive advice.




airstone and bubblers also help by forcing low oxygen water from the bottom to the top. Also, when bubbles hit the surface and open up, they create added surface area for oxygen interface
 
I would like to see some scientific documentation that the water can exchange gases with air in contact with it at the surface, but can't with air in contact with it below the surface.

Well actually - we never need to worry about that, right rbishop! 'cause the bubbles that rise in the water can run - but not hide - they gotta go pop sometime. SO this way, or that. The gas exchange is in!!!!!
like knowing which side of the bread is buttered - I, for one, eat both sides:joke:
 
Dixienut. I liked your idea.
I was laughing (btw) at how rbishop phrased his post. I didn't take it as mean. I thought that a little air exchange did happen on airstone bubbles as well as from surface agitation.
Lv2Padl has enlightend me:
"the reason "bubbles" don't oxygenate the water is because they don't have sufficient 'residence time' and the phenomenon known as 'surface tension'. in other words, the bubbles emmitted by bubblers and such make it to the surface long before oxygen can be exchanged at the bubble/water interface, and the surface tension of the bubble holds the oxygen within the sphere. oxygen diffuses and is exchanged at the surface simply because the residence time is infinite."
I stand corrected.
 
I was told to use air stones attached to air pump...my fish seem to be doing very well they like the bubbles.
 
I totally agree with liv2padl, on the time requirement and temp/pressure issues. Maybe it is semantics. I do believe the circulation of the water and agitation at the surface are added means for agitation that we see repeated recommendations on, when stating you don't need airstones.

I think for most it comes down to looks. I just prefer the look and don't see the need to agitate the surface with mechanical filters when I can do it with airstones.
 
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