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Discussion Starter #1 (Edited)
Pressurized CO2 Questions on post #15

I don't exactly get how it diffuses CO2 into the water... I mean I know that it breaks it up into smaller bubbles, but here's what I don't get:

If we put it under the filter output, even though it blows around the bubbles, they still rise to the top and pop...so how is the CO2 getting diffused?
 

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The gas is fusing with the water, kinda like carbonated water. And if you have too much surface agitation, it's like shaking up the bottle of soda/ carbonated water and it releases the co2 from the water.
 

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I don't exactly get how it diffuses CO2 into the water... I mean I know that it breaks it up into smaller bubbles, but here's what I don't get:

If we put it under the filter output, even though it blows around the bubbles, they still rise to the top and pop...so how is the CO2 getting diffused?
The reason for glass and wood diffusers is to make the bubbles small as possible so that it can dissolve more easily in the water. Why does it dissolve more easily? If you think about it, CO2 diffusion is when a CO2 bubble breaks up into much smaller bubbles. The smaller and finer the bubbles, the more it'll float around the tank instead of shooting straight up to the surface, and the longer it stays in the tank, the more chances it has to be absorbed by plants.

Glass and wood diffusers help this process go faster by injecting really small/fine bubbles into the tank and therefore increases it's intank diffusion efficiency. It is basically doing the majority of the diffusion that's suppose to take place inside the tank BEFORE it the CO2 even gets inside the tank!

So example:

If you pump CO2 into the tank, it can only diffuse each bubble 5 points. So if you inject a large bubble that is 10 points worth, only 5 will diffuse into the tank since 10-5 = 5. So each bubble that comes out, only half will thoroughly diffuse before hitting the surface and only half of it's potential will be absorbed into your plants. Now if you put in a small bubble that's like a 6, then you get the efficiency of 5 and only lose 1 from each bubble since 6-5=1. So you'll still lose 1 from each of those smaller bubbles, but you'll still get the other 5....and you won't lose as much as the big bubbles.

The numbers are just there to give an example and I'm bad at examples. If you still don't understand, tell me and I'll make up another one.
 

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The reason for glass and wood diffusers is to make the bubbles small as possible so that it can dissolve more easily in the water. Why does it dissolve more easily? If you think about it, CO2 diffusion is when a CO2 bubble breaks up into much smaller bubbles. The smaller and finer the bubbles, the more it'll float around the tank instead of shooting straight up to the surface, and the longer it stays in the tank, the more chances it has to be absorbed by plants.
Don't forget, the smaller the bubbles, the more surface area that the co2 has in contact with the water.
 

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Don't forget, the smaller the bubbles, the more surface area that the co2 has in contact with the water.
Yeah, I thought about that a bit but imo, its more in the fact that smaller bubbles rise A LOT slower than bigger bubbles.
When bubbles combine, their outter surface area also slightly increases so that's questionable, but yeah I thought of that.

I also edited the post as well.

It's sorta like melting ice, it's faster to melt 7 smaller ice cubes then melt a big chunk that's 7x as big.
 

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Yeah, I thought about that a bit but imo, its more in the fact that smaller bubbles rise A LOT slower than bigger bubbles.
When bubbles combine, their outter surface area also slightly increases so that's questionable, but yeah I thought of that.

I also edited the post as well.

It's sorta like melting ice, it's faster to melt 7 smaller ice cubes then melt a big chunk that's 7x as big.
Actually, a bigger bubble has less surface area/ volume than a small bubble does. 5 one gram water droplets have more surface area than 1 five gram droplet does, but you are right that they rise slower, but I'm not sure if the rate that a bubble rises at determines how much gas gets dissolved into the water or if the surface area does.
The ice cube example is a good example though.
 

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If you pump CO2 into the tank, it can only diffuse each bubble 5 points. So if you inject a large bubble that is 10 points worth, only 5 will diffuse into the tank since 10-5 = 5. So each bubble that comes out, only half will thoroughly diffuse before hitting the surface and only half of it's potential will be absorbed into your plants. Now if you put in a small bubble that's like a 6, then you get the efficiency of 5 and only lose 1 from each bubble since 6-5=1. So you'll still lose 1 from each of those smaller bubbles, but you'll still get the other 5....and you won't lose as much as the big bubbles
Revised:

I just wanted to add that the smaller bubble should diffuse a bit better because it stays in the water a lot longer.

So for that example, big bubbles would diffuse for only 4 points worth. So big bubbles 10-4=6. 6 will be lost, 4 will be efficiently diffused, therefore you get less than half. Smaller bubbles float to the surface slower so it'll be a 5 or even a 6. So small bubbles is 6-5=1.

Numbers are just there for example.
 

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Actually, a bigger bubble has less surface area/ volume than a small bubble does. 5 one gram water droplets have more surface area than 1 five gram droplet does, but you are right that they rise slower, but I'm not sure if the rate that a bubble rises at determines how much gas gets dissolved into the water or if the surface area does.
The ice cube example is a good example though.
K, we'll say it's both surface area and that the smaller bubbles float to the surface a lot slower :tongue:

Lol thanks for the talk, always nice to have a fellow member to talk back and forth.
 

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It would take a LOT more glass to make 1728 one inch cube aquariums than it would to make one one foot cube aquarium.
1728 one inch aquariums would need 8640 square inches of glass
but a one foot cube aquarium would only need 720 square inches of glass, but their volume would be the same :thumbsup: (generally, I'm not counting glass thickness)
 

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Discussion Starter #15
Ok I didn't want to start a whole new thread, so here's my questions about pressurized CO2:

1. Will this fit a paintball tank?
2. Does the above regulator come with a needle valve too? Is that the gold-colored thing on top of the solenoid?
3. Where can I refill the tanks?
4. What should the PSI readings be at?
5. How do I shut off the regulator and disconnect it from the tank when I go to refill it?

I'm pretty sure I'll come up with more questions later on, so bear with me:icon_roll
 

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#1..NO...it states in the post: SPECIAL NOTE: Aquatek regulators are equipped with CGA 320 connectors, this offers a custom fit for standard U.S. CO2 tanks

#2.yes.

#3 local pressurized gas filler,and sometimes a paintball co.

#4..
I think I run mine 10-15psi..

#5.Shut the valve off on the co2 tank,disconnect the WHOLE unit,set it gently on the floor,then take tank to get refilled,or traded out for a full one..dont forget the washer to go between tank and stem when re-seating.

Kevin
 

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Pressurized..Less muss,no fuss.. :)
 

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Remember,if you go pressurized ,you can upgrade easily,and will be able to move it to any tank you decide to start,no matter the size..
 
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