Question about CO2 in youtube videos etc

[Nick potts]

Question regarding CO2 distribution in the tanks I see online.

Most of the scapers that use in tank diffusers use them at the opposite end of the tank to the filter outlet, and from what I see in a lot of videos, most of the bubbles just go straight to the surface, yet they don't seem to struggle with CO2 and have nice green drop checkers.

I have tried this on a few tanks, and I have lots of flow, the bubbles circle the tank but I always struggle and end up using a powerhead. Am I doing something wrong?

Sorry for all the co2 questions and the many more to follow

 

[GTomas]

I am sure many people swear by these diffusers, but I always use inline diffusers, better co2 distribution, less cluttered and reduced co2 consumption.

Cheers
Tom

 

[Andy Pierce]

Which bit are you struggling with... getting the drop checker to be green? It's not actually the bubbles you want as such, you want the CO2 dissolved in the water (you can't see dissolved CO2 - it's too small). Small bubbles that are pushed around are more efficient at getting CO2 dissolved for several reasons: 1) smaller bubbles have higher ratios of surface-area to volume; 2) smaller bubbles rise to the surface more slowly increasing the time for diffusion to take place; 3) when pushed around by flow the bubbles have a longer path to the surface and thereby encounter more water; 4) sometimes small bubbles get trapped under leaves/hardscape and then have a very long time to dissolve (but for me this last one doesn't really seem to happen). That all being said, CO2 isn't very expensive so instead of trying to be super efficient about getting it dissolved, you can just turn it up with a less efficient set-up and get the exact same results.

 

[foxfish]

Nick, I understand what you are getting at and is something that has puzzled me …. We spend huge amounts of time discussing how best too distribute the C02 buy using spray bars, reactors power heads and other methods and gadgets …. Then you look at some amazing youtube tank with a basic diffuser and wonder ‘how’
Sorry i dont know!

 

[Nick potts]

Which bit are you struggling with... getting the drop checker to be green? It's not actually the bubbles you want as such, you want the CO2 dissolved in the water (you can't see dissolved CO2 - it's too small). Small bubbles that are pushed around are more efficient at getting CO2 dissolved for several reasons: 1) smaller bubbles have higher ratios of surface-area to volume; 2) smaller bubbles rise to the surface more slowly increasing the time for diffusion to take place; 3) when pushed around by flow the bubbles have a longer path to the surface and thereby encounter more water; 4) sometimes small bubbles get trapped under leaves/hardscape and then have a very long time to dissolve (but for me this last one doesn't really seem to happen). That all being said, CO2 isn't very expensive so instead of trying to be super efficient about getting it dissolved, you can just turn it up with a less efficient set-up and get the exact same results.

Hi Andy.

It's not so much I'm struggling (though I kind of am), I get a 1.2ph drop but it's a very high rate of injection on a small 30ltr tank. The drop checker is green but no as green as I would like.

I have tried all sorts of ways of distributing CO2 and have gone back to a powerhead for testing, the bubbles are already tiny out of the twinstar diffuser and then are mashed up more and spat out of PH around the tank. They don't get stuck under hardscape etc for me either, i think the flow is too strong for that.

Nick, I understand what you are getting at and is something that has puzzled me …. We spend huge amounts of time discussing how best too distribute the C02 buy using spray bars, reactors power heads and other methods and gadgets …. Then you look at some amazing youtube tank with a basic diffuser and wonder ‘how’
Sorry i dont know!

That's it exactly.

It just appears to me that most of the co2 is lost to the atmosphere, yet they don't seem to struggle and are only using a low injection rate, just seems counterintuitive. Of course, it could be that they just change things for videos on a lot of channels?

 

[Angus]

The only diffuser that ever worked for me was the neo style with the ceramic plonked ontop of the glass part of the diffuser, these youtubers probably don't care much about how long their bottle lasts as they probably have 5 more sitting in a store room waiting, so if the drop checker isn't turning they just increase the BPS, money is no object as they say.

The drop checker is green but no as green as I would like.

Out of curiosity can you push your drop checker to a yellow colour if you put your diffuser in a bowl of water with it?

 

[Nick potts]

The only diffuser that ever worked for me was the neo style with the ceramic plonked ontop of the glass part of the diffuser, these youtubers probably don't care much about how long their bottle lasts as they probably have 5 more sitting in a store room waiting, so if the drop checker isn't turning they just increase the BPS, money is no object as they say.

Out of curiosity can you push your drop checker to a yellow colour if you put your diffuser in a bowl of water with it?

That's the style I use, they are the twinstar/aquario ones and the bubbles are very fine.

The bubble count is already very high (8-9bps) and while I don't care how much I use it just makes me think something is amiss. When looking online, even tanks double or triple the size of my tanks run and much lower injection rates and with relatively lower flow (I know all tanks are different), and this is just me trying to figure out the puzzle of CO2.

I just can't figure it all out, I would say I have to much flow in my tank, the co2 is whizzing around the tank very quickly, is that causing a problem? Is it the surface skimmer? And just when I thought I was happy with it/