Disgusting Film All Over Tank

[LittleWatty]

My fish Sonas is fine as far as I can tell, but I really want to know what's going on with this really nasty film that keeps showing up in his tank. Anywho, here's what's going on. The past two weekends I've been out of town with extended family, and each time I come back after a few days to find this icky white substance coating the surface of the water, and anything at or above the surface (like my heater's cord, or decorations). The only thing I can think of its a build up of stesscoat as the water evaporates (we've had 90+F temps out, so I have a fan blowing across the top of the water to speed evaporation and keep the water cool). It hasn't happened in my cycling tank (which has since finished, and is currently housing Sonas), but its happened twice in a row in my 3 gallon. It doesn't seem to have hurt Sonas while he was in the dirty tank, as far as I can tell, but it did really stress him out, and even more so when I'd change the water for him.

Here's as many of the questions as I can answer that are relevant.
Housing
What size is your tank? 3 gallons (my 6.6 gallon has no issues)
What temperature is your tank? 80-84F (I can't get it any cooler without using ice cubes)
Does your tank have a filter? No (the 6.6 does)
Does your tank have an air stone or other type of aeration? No
Is your tank heated? Yes
What tank mates does your betta fish live with? None

Water Parameters:
Have you tested your water? If so, what are the following parameters?
Values at last check:
Ammonia:0ppm
Nitrite:0ppm
Nitrate:20ppm (from tap)
pH: 7.4-7.6

Maintenance
How often do you perform a water change? 100% 2 or 3 times a week, depending on the water. I did 100% changes before each weekend trip.
What percentage of the water do you change when you perform a water change? 100%, as stated
What type of additives do you add to the water when you perform a water change? API Stresscoat and a little aquarium salt (for a missing scale issue that's since been resolved, and am reducing the amount used slowly)



I want to repeat that, as far as I know, Sonas is in no danger. I just moved him to a 6.6 gallon tank that has just finished cycling, and is planted, and I've never had any issues with this tank. Its just the 3 gallon that I just moved him out of that kept having this issue.

[Sena Hansler]

Try removing the heater... See if it stops. If it doesn't, good that is not the culprit. I am used to 1. heater snot. Icky, gooey, slimy stuff. OR 2. protein film. It could very well be the heater (or heater snot :) ) Is there any smell in there? Like, rubber, decay, rotten eggs, sweet, etc?

[LittleWatty]

It just smelled like fish. Since Sonas is no longer in that tank with that heater, I might just run a test to see if it is the heater that's causing it. It seemed too extreme to be a buildup of stresscoat from water evaporation XD I thought protein film was just from uneaten food decaying? If that's true, then it's not that, as this was during a several day fast. From Thursday to Sunday/Monday in both cases

[WetBetta]

Is it possible that the fan you turn on above the container is blowing something onto the surface of it? Dust or anything? What is is behind the fan or on the fan blades? As I understand it, it started when you started turning the fan on.

[LittleWatty]

There was a film on the water before I even bought the fan - but it wasn't to the extent that it was those two weekends with the fan. Didn't even think of that one time when I originally posted. There really is nothing behind the fan - pretty much just the wall.

[WetBetta]

Try leaving the fan off and see if it happens. If it doesn't, turn the fan on and see what happens. Sounds like something in the air there because you've had this film... an ongoing film that got worse when you put the fan on. Is the wall behind the fan stucco'd by any chance? Is the paint on the wall old? Look at the blades on your fan... wipe your finger across one if you can... see what comes off the blade. Is it like a white powdery substance?

[Sena Hansler]

Protein film isn't just from uneaten food. It's just whatever is in the air or water, and is more usual in stagnant water.

[TuckerLove]

Im not going to lie but that second pic made me gag a little...I hope you figure it out :) I have no idea lol

[Tikibirds]

I was gonna say protein film as I get that on all my smaller tanks with no filters and it can get kinda thick but not THAT thick. I have wondered if stress coat adds to the film. If i use Amquel plus or prime I don;t get the film nearly as bad as I do when I use stress coat.

[Twilight Storm]

That is pretty nasty.

I have no idea what it is, but I agree it might be a combination of the fan blowing something into the water, the water evaporating, and the stress coat aloe vera congealing somehow into that mess.. It does look like someone had a bad cold and decided to use the tank like a tissue.

I only use stress coat in much smaller then the recommended amount (Just a few drops on top of normal water dechlorinator if needed.) because things I read said it can gum up their gills... Your picture makes me think that may have a hint of truth in it. I will definitely be stalking this thread to see what it turns out to be if you can figure it out.

Why would a heater cause that to happen?