You answered you own question.

It is better to clean reels with a soak in dilute bleach in my experience. Bleach will remove any residual gelatin along with any stains. If you use Photoflo, don't let it touch the reels. If the film is sticking you probably have some residue. I use Jobo reels and I literally just push the film on them. If the reels are clean, I never have any problems.