LOL I'm all over the place! I've read & read about the external
pumps, priming pots, leaf traps, etc. I have a few reservations and
am more leaning to the point of not spending the time to create the
housing, etc. required.

I think I'm going to stick with the pondmaster mags which can go in or
out.

OK - NOW.... I've flipped from using a 45g garbage can to doing this
right and getting a 70g Rubbermaid stock tank. I can pick this up
locally for $54.98.

OK. I will now have:

70g biofilter
2 feet drop of waterfall
1.5-2' stepback from pond edge to fall top lip
1200-1500 pond approx 2' deep

The hose from the pump in the pond will have to travel at least 4 feet
high and 4 feet long. I'm going to use flexible hose so there
shouldn't be any elbows.

So if I get a 750 gph pump just for the biofilter - wouldn't by the
time it got to the source then had to deal with the biofilter -
wouldn't the actual numbers on the 750 gph be greatly reduced? I.e.;
wouldn't I end up spitting out more like 400 gph by the time it spills
out the biofilter?

I'm just ready to make an online purchase and am concerned about what
size to go with that will do the trick to keep a clear pond year
round. I won't have much opportunity to have plants.

Sorry if I'm being a pain, but I appreciate the help.