Put in only three loaded reels and an empty spacer reel on top, and use just enough solution to cover the three loaded reels.(posted 8616 days ago)Invert it briskly two to three times in a five-second period every 30 seconds, or 10 seconds every minute if you prefer. Forget toroidal and don't be gentle. Be sure to give 30 seconds continuous initial agitation.
The problem you describe is caused by insufficient agitation.