Just curious about slime...
 

I was recently doing a 50% water change and noticed that my ornaments were slimey and slippery to the touch. Is this the good nitrite nomming bacteria or just algae, should i scrub it off?
Cheers

If you can actually see it, I would suspect it is algae or (I hope not) cyanobacteria. The latter occurs as green sheets of slime and is actually a bacteria although we generally consider it within the algae group. I have wood and rock in my tanks and allow any algae that wants to settle to do so as it looks natural. Keeping it off live plants is critical.

Nope totally invisable...