I'm using Aqua Pearl, similar to DE but without the silica, in my big Quad filter, 80 sq ft. It is backwashing out better than cellulose did. When I backwash and run pump on the usual, 19-20 gpm, which is pretty low flow, after backwashing the psi is 3-5. When I take filter apart and clean, it is just a little under 3. If I increase the pump speed psi is higher than that and goes up as I run the pump faster. Any of the three common filter media for a DE filter, cellulose, DE, or Aqua Pearl, all give a just below 3 psi when the filter is opened and cleaned when filtering at 19-20 gpm.
I'm not sure what the ball park figure would be in terms of comparing the 10-20 gpm to a certain HP, and/or fixed speed pump. I do not have very high head on the system.
gg=alice