fuel filter info plezz

[imiitek]

how restrictive should a fuel filter be

i have removed the return pipe before the fuel pressure regulator in engine bay
and have removed the feed pipe from the fuel pump and tried to blow threw it and seems like it has a very hight resistance i cant blow anything threw it

and a lot of gunk coming out

checked the fuel tank its clean the gunk seems to be in the fuel line


any help