I know this is going to sound funny, but it is a serious question. The last few times I have dumped the tanks on our 26' travel trailer, I have noticed the usual smell coming from the hose as the black tank empties, but then a very strong smell coming out when I drain the grey tank. I know that these are not designed to smell pretty, and I don't expect perfume or roses or anything, but such a strong odor from the grey tank makes me think: "Bacteria". Anyone have any ideas, suggestions, solutions? Am I just worrying needlessly? Should I just buy a quality pair of noseplugs?