The Koralin systems Ive seen use Eheim pumps, so that's good. The prices are at least $400, so a complete system for that price is not a bad deal at all. Do Koralin reactors work better than anything else? I think it would be difficult to make a CA reactor that did not work based upon the theory of what actually happens. They are basically a tube that recirculates water over and over through the tube. A valve at the top allows you to control the CO2 and output of the reactor. Would you benefit? Sure.