Thank you for the input!
I seen claims for both it being harmful for the bio filter and for the pump impeller but I did not see any first hand information on this.
Since the condition (pH) of the water leaving the filter indicate about 30ppm and the fact that the bubbles seems to absorb fairly well I'm not that worried that it would be harming the bacteria. The condition in the filter should be the same as if I have 30 ppm in the tank, right?
In regards to cavitation damage I think there is some confusion on that. Cavitation damage or erosion occurs when the pressure is the liquid is so low that you for a vapor bubble that then collapses at or near the surface resulting in very high pressure spike that is deforming the metal. You can also get cavitation driven corrosion on materials like stainless that is protected by oxide layers. To collapse a CO2 bubble would require you to dissolve it and that is not as fast of a process as collapsing a steam bubble that is condensing into liquid so I don't think it is likely to happen.
I have however noticed that I do get burping now and then when I am increasing the flow rate of the CO2 trying to get 25-30ppm in the tank so I will probably pick up a 10" filter housing and make a in-line reactor.
I did order a Sera Flore CO2 Active Reactor 500 a few weeks ago from Petco but after 10 days seeing it show as "In progress" and twice calling just to talk with some clueless customer service people I cancelled the order and will go with a DIY reactor instead.