Fletch, I hate to say it, but I think you're up against one of the core problems with drip systems- and the main reason I no longer use one.
Nutrient solutions form crystals wherever the solution is exposed to air and water can evaporate- on the sides of rez tanks, on hoses, etc etc... but worst of all- crystals form in the small apertures used as drippers or sprayers. No amount of filtration will stop these blockages as the nutrients are totally dissolved and will pass right through a filter. The nute salts are most likely crystallising on the drippers after they have passed through your proposed filter.
I gave up on drippers and sprayers and just used small diameter plastic tubing (about 4mm ID). The solution dribbled instead of spraying, but worked OK. However, algae grew inside the tubing and was a general pain in the ass to clean
I eventually gave up in drip systems altogether and now use a flood/drain system with plants grown in plastic pots stuffed with loose rockwool floc.