After mixing fresh Dektol about a week ago, I filled four one liter brown plastic bottles to the top for storage. As of yesterday, it had all turned brown, like dark brown, but still seemed to work okay. So, obviously, the brown plastic bottles are no good for Dektol storage. Will they be usable for other stuff or should I just throw them in the trash? How can you tell what plastic is safe for photo chemistry? All of my other bottles are super duper brown glass that I snagged from the trash at a state environmental lab. Might have to hit the dumpster again!