Co2 Into Uplift

[elmo666]

Hi, I have pressurised co2 on my discus tank set up as per signature. A friend at my lfs suggested that letting most of it enter the uplift on my external would give an increased contact time, and as a result better absorption. I do have my plants pearling quite nicely. Only thing is I occasionally have a sudden discharge of fine bubbles from the return, which I assume is the co2 building up in the filter. I now have a few concerns. Firstly, could I be starving my filter of valuable oxygen? If the co2 is building up in the filter can there be any harmful interaction within the filter? Sometimes there's fine particles as well making me think the gas is "floating" detrius away back into the tank. Am I worrying too much or should I refer back to it simply entering the tank?

 

[Zikofski]

personally i think you are overthinking this a little most some people use inline co2 diffusers like me and some have it on the intake myself have it on the outtake so i don't have the issue u speak off but until your cycle is effected then u should have nothing to worry about. just keep to what u have been doing especially if i have been getting perling

 

[elmo666]

Thanks. I'll try to switch off a little more.

 

[elmo666]

Just google the inline diffusers, I like the sound of them!! Added bonus of getting the glass diffuser out of the tank, won't get a build up in my filter. Will order one tomorrow. Thanks again

 

[bricko]

2nd vote for inline diffusers, less equipment in the tank and if you set it up on your outflow you wont get 'trapped' C02 in your filter building up.

 

[TwoTankAmin]

I ran pressurized co2 for about 12 years. Due to space considerations I could not run a decent diffuser. I decided to run the co2 directly into the intake of my Eheim Pro II 2026. I chose the Eheim brand specifically to be able to handle this. I felt it would stand up best to the gas going through the filter and occasionally building up there causing some cavitation.
 
Every now and then the spraybar would burp a bunch of bubbles. I took down this tank in early 2013 as I was not willing to spend the time and effort to keep it up. The canister is still running silently today on another bigger tank.
 
So if you do not want to go the diffuser route, I can attest to both the effectiveness and durability of Eheims to do double duyy as a diffuser. I would never attempt this with another brand of filter. Just one man's opinion.

 

[elmo666]

Thanks two tanks. I'm not really concerned too much about damaging the filter in a mechanical way, more so worried about the filter colony and the potential lack of oxygen if co2 is building up within the canister. Last two days I've paid a little more attention to the filter, listening to it. It becomes gradually a little noisier before the gas is discharged from it. Last night, 4 hours after the co2 went off, I gently rocked it......the amount of built up gas was quite alarming! The downside of this of course is that I'm going to get co2 dispersed long after my lights go off. I think I'm going to have to get away from the uplift idea and use an inline diffuser on the return, which I'm going to set up low level in the middle of the tank. The more I think about it, and knowing my co2 level is quite high, it cant be of any benefit to the filter colony sending it through there.

 

[daizeUK]

I run a yeast CO2 setup and thus unable to use inline diffusers due to lack of pressure.  Placing the diffuser under the intake pipe is a good way to improve CO2 dissolution and this is exactly what I do.  I find there are no problems with burping as long as the bubbles are small.  Keep the bubbles fine by cleaning your diffuser regularly.  I bleach mine every week.  My filter is a Eheim Classic with mixed sponge, ceramic and wool media.
 
Sending CO2 through your filter won't harm the bacteria.  CO2 does not displace O2, that's a common misconception.  When fish asphyxiate due to high dissolved CO2 levels it is not because of lack of oxygen - it is because the CO2 cannot pass from their bodies out through their gills.  In effect, too much CO2 stops them from being able to breathe out rather than anything to do with oxygen.  It's a strange concept because as air breathers we never need to worry about breathing out, but for fish it's a problem both ways!

 

[elmo666]

Thanks for your input, very helpful. I had no "burping" issues before I upped my co2 to 6 bps in an attempt to put a stop to bba that has appeared. Having hair algae issues as well. Have to take a look at my ferts next, either too few or too much??? Never straightforward lol