Fresh water tank

I think a foreign body may be lodged in the fresh water tank on my Kemerton XL. The pump strainer contained a black substance and when I flushed through the tank numerous black “feathery” black pieces came out. I have put tank cleaner in and continued to flush through but want to be certain nothing is left.

I notice there is a rigid L shaped piece coming out of the tank onto which the blue flexi hose is attached by a jubilee clip.

Advice please on whether thus L shaped piece cane be removed and if so how and if it can will I be able to get a hose into the aperture to achieve a direct water hose?