I developed three roles of film in three different tanks and they all turned out the same greenish cast on the emulsion side and gray on the plastic side.
I checked my exposure, temperature, development time, and sufficient agitation were all correct.
Could the D76 developer stock (diluted 1:1) was too weak? I used 11 min for Ilford HP5 ISO 400.
I used a Patterson two reels tank system and loaded one reel with film and inserted the second reel without film. I used a total of 10 OZ of working solution. Perhaps the problem was loading the empty second reel that prevent the 10 OZ of working solution to properly develop the loaded reel.
I did not mix the D76 and is available in a shared darkroom (without supervision) in a community college.
The fixer is in a 10 gallon tank. A second 1 gallon container is used for film and paper. I tested and checked the fixer and it was not cloudy. I fixed for 8 min., Agitate first 30 second non-stoop. Agitate 10 seconds each minute. Also used Hypo for 2 minutes.
I agree with the other comments - it appears to be poorly fixed film. Matt's suggestion as to how to test fixer is one I use often.
Re-fix in freshly made fixer, wash, use some Photoflo and I'm pretty sure you'll see the difference immediately.
All kinds of strange things happen in shared darkrooms. Well, strange things happen in my personal darkroom, too, but that is entirely a different story!
Look at the margin of the film. If fixer worked, that part, unexposed, will be totally clear. It isn't. That means fixing process didn't work for whatever reason.