Brown Residue?!

[FroFro]

I came home from work to find a fine layer of brown residue on the rough surfaces of my ornaments, on the underside of the plastic leaves on my plants, and along the plastic parts of my aquarium heater and filter intake. None of the glass has this residue. My fish seem to be fine and active. I don't think it's diatoms as I've googles as the picture makes it look like some kind of hairy brown algae. It's almost like a slime coat in the tank. I run my fingers along it and its slimy and its rust brown in color. I'm currently scrubbing my ornaments in hot water and removing everything but the substrate and fish and doing a massive gravel vaccuming. I'm a bit worried as I've no idea what would've caused this. I did my usual forty percent water change/gravel cleaning on Thursday. I have not added any new fish, chemical, ornaments or the like. Simply conditioned water. I have my fish on a strict feeding schedule of every two days. I took a small cup of tank water and tested it with my kit, my readings are coming back at 0 and a Ph of 7.3. I've checked my filter and have found none of this brown stuff inside it, but I'm going to give it a good rinse in clean water just in case. I'll supply a picture if I can once I get done cleaning all this!

 

[SnailPocalypse]

Possibly algae?

 

[NickAu]

Is this a new tank?

 

[FroFro]

Is this a new tank?

No, its my established 36 gallon bowfront. Water parameters are all reading fine, tank is cleaned regularly with two forty percent water changes a week. Fish fed a specific amount of food once every two days. Gravel is also vacuumed regularly. I have NO idea where this residue came from.

 

[flchamp89]

Led or florescent? Bulbs old?

Sent from my SAMSUNG-SM-G890A using Tapatalk

 

[angelcraze]

Does the slime have any odour? Undersides of plastic leaves is odd....

Diatoms are not hairy. They can become so, but I feel when it gets like that, it's on its way to becoming BBA. Straight diatoms are a bit slimy, but wipe off easily and is more of a dust than slime sheets.

 

[FroFro]

Led or florescent? Bulbs old?

Sent from my SAMSUNG-SM-G890A using Tapatalk

LED, I bought new bulbs when I bought the tank/hood combo the lights are only about six months old. I keep the lights off for half the day.

 

[FroFro]

Does the slime have any odour? Undersides of plastic leaves is odd....

Diatoms are not hairy. They can become so, but I feel when it gets like that, it's on its way to becoming BBA. Straight diatoms are a bit slimy, but wipe off easily and is more of a dust than slime sheets.

I noticed an odd sort of... musty water smell on my fingers when I touched the residue but my aquarium itself didn't have any odd odors coming from it.

 

[angelcraze]

Are you still having issues?

Would it be possible for you to do a 5-7 day complete blackout? This means covering the tank with garbage bags a dark blanket for the top to allow oxygen exchange and no peeking for 5 days.

Is probably not, but there's a possibility the brown stuff is cyanobacteria and not a true algae. It will die off with a blackout. With plastic plants it should be easy enough to do. If it is an algae, that will die of as well, but at least you are preventing a cyanobacteria issue that way.