I thought you were not supposed to run them on a timer? I have a 620 ant it is great. I remember the instructions not be very good on showing how to configure it like a tunze pump but it can be done.
*180 gal Display, 100 gal basement sump, 33 gal refugium, 3x250 MH, 2x160 VHO actinics, zoos, some softies, LPS & lots of acros and other SPS.
*100 gal prop tank plumbed into main system w/ 2x96 PC lights and 1x150 MH,