Good method of diffusing CO2?

Just so I'll know, how does a gas hurt the impellor of a filter? Does it damage itself from lack of resistance?
 
My guess is they think the bubbles causes the impeller to vibrate when the bubbles hit tie blades.

And with all moving parts, vibration is bad.
 
Thanks.

I had diy going into an aquaclear for almost 3 years and it was ok. I am planning on getting an in-line solution but am running it through the filter for the time being.

I'll let you know if it breaks, it's an eheim ecco.
 
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