If you pull that washer tank out you should be able to see the pump and the lines to the windshield... rear... and front washers. Make sure those connections are good. I would look at those anti back flow "things". I had one go bad on me... leaked terrible... plus loss pressure to the rear washers.
If you run washer fluid mix in there you might want to make sure there is not a build up of junk clogging the fittings. Free to do!