Yellow Growth On Tank Filter - What Is It?

[Perpetualcoolness]

Hello, I have already asked this question in another, older, thread but, following a member's suggestion, I am starting a new topic with it, to see if anyone knows what this is.

We are new to fish keeping, couple of months really, and we started off with 8 fish in a 40L tank but, sadly, we only have two left, a neon and a betta. The others died gradually. I have taken some advice from members in this forum, and have been applying it, and the tank and two fish left seem to be stable now.

I noticed yesterday that the filter and sponges on my 40L tank are covered in a yellow gunk which seems to be spreading to the cables around it, today. I have only rinsed the sponges during a water change and just pretty much left it alone, but what is this yellow stuff? Some fungus? Do I need to clean it off? I have not yet touched it as I don't know what it is.

I would be grateful for any advice, please. Here is a photo of the filter.

 

[fluttermoth]

Oooh, it's a kind of slime mould (sorry, I'm fascinated by slime moulds 

)
 
It won't do your tank any harm, but it's of no benefit either. I'd clean it off as it does look unsightly.

 

[Stimo]

i've seen this somewhere before but can't think where

http/www.bbc.co.uk/nature/19846365

 

[Perpetualcoolness]

Thanks for your feedback. Appreciate it. When I got home this evening, the yellow mould was actually reduced to a third! There's still some left around the back corners of the filter box but what was all over the sponges and cables is pretty much gone. Don't know why but glad it's gone as it was gross.

Fluttermoth, do you know what causes it? Don't want it coming back

Thanks again.

 

[AmyStroodle]

That looks scary and infectious. 0.0