Hello everyone, I recently ordered some plants and was setting up a 10g quarantine tank to keep them in after sterilizing them. I kind of jumped the gun and set up the tank a little on the early side, so I figured I wouldn't bother dechlorinating the water just yet and would just change the water out closer to their arrival. Well, my plants are now on their way and I drained the water out of the tank. Everything was so ominously foggy. I wiped the aquarium glass and got this strange residue. It can't be diatom algae since the water was still chlorinated, right? Or can this algae somehow survive that? Admittedly, the tank is next to a window, but I'm a cave dweller and don't open the blinds. Is it algae? Could my new heater be leaking something? It's just a little freaky to me.