Containers can be cleaned with either water or Windex with Ammonia-D. Spray down the surface of the container where it is dirty and use a lint-free cloth or sponge to wipe the surface. It may take several cycles of wiping and drying before the container is completely clean. This is normal and to be expected with the texture in the fiberglass. Do not pressure wash, use alcohol based cleaners, apply corrosive cleaners, or clean with anything abrasive.