"Chris" writes:

I want to make sure nothing big gets sucked into the pump. I did this
originally to catch the big stuff so it would not get sucked into the pond.
The problem is it has to be cleaned to often. I want a big prefilter and
would not even need the ptrap at that point.

Yep. I retrofitted a settling tank (a 32gal plastic trashcan)
to my filter, loosely stuffed with bird netting. ALL the visible
stuff is caught and I clean it once a year. The bird netting acts
to slow the water flow so the particles drop out. The mesh is so
large (3/4 inch) that it just never clogs :-)

The next stage is a biofilter with plastic gutter screening and then the pump,
through the UV and back to the pond. Once a year maintenance.