When you do replace or repair the tube simply wash the wheel and tire out really good. If you break it down yourself be sure you have the wheel assembly somewhere where "gunk" isn't going to hurt/stain anything...it can be messy. Have you mounted one of these small tires before?
If there's any rust or corrosion showing on the inside of the wheel scrub it down with a wire brush and put a couple of layers of spray paint on it. Pay close attention around the stem hole area. At some point in time there will most likely be some rust between the tube and wheel anyhow due to condensation between them...no biggie. The sealant, though, can take it to a point of messy corrosion if left in there long enough....plays heck on aluminum and chrome plated wheels, too.
