This science project seemed to work out well. I used the Anthony Sylvan brand cartridge cleaner and mixed 4 oz. to 1 gallon of water. There are also spray bottles of solution which is washed off after a few minutes but I don't have any so didn't try it.
First I submerged a little less than 1/4 of the filter in solution vertically for 5 hours. When I pulled it out to look at it, dirty solution just drained from the filter...doesn't get much easier than that. I rinsed it with a garden hose spraying from the inside out to flush out any remaining solution. Then I flipped it 180 degrees and let the other side soak for 12 hours to see if a longer soak would make any difference. I don't see any difference. The filter element, metal and orange casing all look the same in fact the orange casing and metal look exactly the same as the areas that did not soak. I waited about 36 hours to let the filter dry before taking pictures. My filter wasn't excessively dirty but you can see the dirt in the solution which was clear when I started. I don't know how similar the FA 50 filter material is to the repo's but these results look promising. If you want to try it, start by soaking the smallest section possible for 1-2 hours and then have a look at it. If it's cleaning as expected, do the whole filter. If not, you can always turn that small section of filter to the rear where nobody would see it if your using it for show.
For comparison, I put a piece of standard notebook paper (thinner material) in and let it sit for 24 hours to see if it would deteriorate. The blue and red ink lines dissolved but the paper remained in tact.
I already have a new filter but if I had to, I wouldn't hesitate to use this one again. The next time I get Evaporust, I'll toss the filter in to see if it affects the paper at all.