My son had an iliostomy for a year. He had the same problem that you experience. What helped him was, we would put a thin maxi pad in the bag. This would absorb much of the liquid and keep it from sloshing around and irritating his skin and causing the wafer to unattach. Anyway, if you haven't tried that, maybe it's worth a shot. Now days, the pads are thinner and more absorbant too. Good luck!