White cobwebs growing on gravel and glass

[Jinnitt]

I have a tropical fish tank and have noticed white sort of cobwebs growing out of gravel and on glass. Would anyone know what this is and how to get rid of it please.

 

[Colin_T]

that's cool

 

[howard_hopkinson]

It's a plasmodial slime mold as far as I can tell, though which exact species I don't know. They are not harmful to fish. From what I can gather, the only way to completely remove it is to break down the tank and disinfect. I agree with Colin_T it does look rather cool.

 

[TekFish]

How do you get a plasmodial slime mold in a tank even. I've only ever seen them in forests and stuff before. Did you use soil as a substrate?

 

[Barry Tetra]

It does look cool

 

[Jinnitt]

I used tetra substrate and also used rainwater from water butt . It comes and goes the one in the picture is disappearing.

 

[howard_hopkinson]

In that case, my guess would be it's in the water butt and that's how it got in your tank.