Koi. No bottled bugs, nothing else fancy, just Koi. Low feeding (but slightly increasing), moderate water changes. With the K1 (in Nexus) it "cycled" the first time in roughly 4 weeks (27 days) and the second in roughly 3 weeks (22 days). Prior to K1 and using submerged airated matting, it has always been right at 6 weeks.
By letting the filter cycle using this method, I feel that the balance in the water chemistry will be more consistent with long term operating parameters. But hey, maybe its just me
Steve