price is not really a problem but keep in mind i have a other stuff i have to buy. but i want to know what the best skimmer is that hangs on the back i have a 55g tank
The HOT-1 is a much better skimmer. I really don't think the BakPak would suffice on your 55, but the HOT-1 certainly should. It is built a lot better and will pull out much more gunk with no modifications.
Have to pipe in with my personal choice, the AquaC Remora Pro. I prefer the remora because it doesn't rely on a venturi like the bakpak does. As I recall the bakpak uses a Rio ventury pump, which is reason enough not to buy it.
I don't know enough about the PM-1 HOT skimmer to say whether it's good or bad.