started growing on the bottom of the heaters and the rubber parts if the input and out put of the fx5 i havce running on the 125g. what is it? i have seen ghost shrimp eating it.
THIS IS SPARTA!!!
Sorry, just couldn't resist.
On a more serious note, I can't really tell what it is. Looks like some sort of algae, but again, I'm not really sure.
I don't know what it is, but I get it from time to time on my brackish tank. Only around the heater. Doesn't seem to harm any of the fish so I just leave it or scrub it off at water change.
I have had tiny pieces of polyfill come out of my filter when I did a DIY stuffing on my AC110. The little pieces accumlated in little localized areas and it looked exactly like that. The stuff appears organic until you remove it from the water. Even the way it accumulated in only one little spot in my reasonably large 140gal even seemed organic.
I put a better post filter on my rig to contain the polyfill a bit better. (used black plastic gutter guard)