Low presure and dirty dishes

Low presure from the pump. If I open the washer prior to washing and add water the unit seems to run much better. I have noticed glass and other junk jammed in the bottom of the unit. I have tried to remove the top of the filter assembly i guess but have had a hard time getting the middle bolt out. Is it clockwise or counter clockwise ? When I get that out I think I should be able to remove the housing and remove the crap from the filter I hope. Is the low presure from the pump caused by this stuff being in the way ?

Thanks for any and all help