I have a CO2 reactor that looks like this ... I'm struggling to get my CO2 levels up and I'm not sure if it's the way I've got the reactor set up or insufficient flow around the tank. I've got large bubbles rattling around at the top of the reactor (B) and a big blob of CO2 in the bottom section with large bubbles rattling around (A). I'm driving it with a 300lph Ehiem Compact powerhead at the moment. Apart from the standard 1000 l/h powerhead on the filter, I also have an internal filter rated at 700lph. The reactor is at the opposite end of the tank from the filter box, the internal is directed toward the reactor to try and spread the CO2 around. At around 1 bubble/sec in a Rio 300, I'm struggling to get out of the blue on the drop checker. Any suggestions?