Thanks all, I've been processing mostly Reala 100 in D76 straight and 1:1, but scanning most to grayscale. I doubt the small amount of coffee did much developing, but may have taken some of the magenta out of some of the images.
Another thing I do is pre-wash for about a minute with water which always pours out slightly magenta and I count that in the development time. 1:1 D76 has been more consistent than straight, but one time I used straight, I got a very high contrast overblown look that I've been trying to replicate. I usually shoot Reala at ISO 50, and 200 and 400 films at + 2/3 EV. I just use a water stop, and do a hypo rinse at the end, with about 10 minutes rinse/soak with soft water.
Filtering the coffee is probably a good idea if the coffee isn't fine enough to completely dissolve.