Thanks for the response. Our filters are very high on the walls. One is in our vaulted great room 15' in the air and the other is on an 8' ceiling upstairs.
In doing more research, I see that the blue filter is an excellent filter to use with a HEPA (so I see what Bolton was talking about now). I'll look into getting a HEPA when we redo the cooling system (should be soon).
Is it possible to change a wall/ceiling mounted 1" filter box to a 5" box or is this something that should be at the furnace?