Personnally, I prefer external pumps. I believe that they have the best warrantee (many with 3 years.) They are easier to maintain and are much safer. No electricity in the pond to harm you or your wet pets. And as for dependability, I don't think you can beat them. I've run a Sequence for 8+ years Seasons) 24/7 with no problems. I also have a Evolution 5500 gph like Steve sells and uses and it is more efficient than the Sequence and pumps more GPH in my configuration. I also like the Supreme Pondmaster pumps too they can be either submerged or external and have cheap aand easily replaced parts. Mine are the 1800 and 2400 gph mag drives.
