For my ATi BM skimmer, I replaced the mesh wheel with a pinwheel from Neptune. It had stalled numerous times with undesirable results. I attribute this to the fact that the mesh migrates in time and can easily catch and bind the impeller. Some folks just take it out and trim the tag ends as part of routine maintenance. I don't like that approach very much. Since replacement of the impeller, it's been running constantly every since. I'm pretty sure that skimmers of this design tent to have restart problems no matter what one does. I've been told that rotating the motor 180 degrees is another mod. that helps. I tried that but found that there insufficient clearance between the motor housing and the bottom place of the skimmer for me to buy that approach. So far, so good. BTW, the BM skimmer still has an issue with setting a proper level of flow through to insure consistent results. What I mean by that is that if the water level in the sump varies by more than about a 1/2 inch, the skimmer either gathers no organics, or it gathers a full load in less than a day and is overflowing back into the sump. It's a little like you have to hold your tongue "just right" and set it and pray for good results.