What is this white/grey-ish film thing on my heater? It's right between the glass tube and the "head", so I'm afraid something might've leaked. If it was just algae or some kind of biofilm, I'm pretty sure my snails would eat them right?
My heater is the Eheim Thermocontrol. It's only 8 months old.
ps: this is for a freshwater tank, but I figure I'd ask here since it seems like many here have experience with eheim heaters (and heaters in general)
