Ok, so its been over a week and I think I need to get my clean on. on the 5 carts ive used I already replaced the stock filler with blue foam. I am going to use 70% Isopropyl alcohol to sterilize the carts but what about the foam? Am I ok to use the alcohol on the foam or should I just rinse with water. How do you guys clean your carts and/or filler?