co2 diffuser fire extinguishe

This is my setup, I've added CO2 setup and this is one week in.   Note, there is no solenoid yet, it's on order.   The CO2 is set very low so as not to send anything off the rickter scale, i.e. the plants were more or less static until now.   Sorry I only have a few Neons and Red Ember Tetras...