Illness, Health & Nutrition • Something really weird going on, need help!

[emacman]

I am a fairly experienced aquarist and cichlid guy. But I've run into something I've never encountered before. Here goes:
I bought a 90 gallon bowfront tank. It has previously been used as a salt water tank. It set in the garage about 4 months before could get to setting it up. I thoroughly cleaned it out rinse several times and then cleaned it wish water and vinegar. 90 gallons water to one gallon of vinegar. So far so good. I left town on vaction and when I returned the almost empty tank (low amounts of water the Python could net get to) has what looks like jellyfish everywhere! I filled the tank up again to reclean it and this stuff is not going away. It looks whitish gray, free floats like a jellyfish, and is extrremely sticky and sticks on everything. It looks like mucos or something. Has any body ever ran into something like this and if so what did you do about it?

Just to clarify the tank was left empty with obviously no fish, no substrate no nothing! But when I returned it was like this stuff had bloomed everywhere. Please offer any advise you have.
Emacman

[GTZ]

Sounds like you grew something.
Bleach/water in a 1:10 dilution should take care of it, let it sit for a day, drain, fill with water and double dose dechlor and let sit for a few hours, drain, soak up what's left if you can't tip to empty and allow to air dry before final fill.

[emacman]

Thank you very much! As I said I've had 50-60 tanks over the years and have never seen this kind of crud before. I'll try your suggestion and see how it goes.
Emacman