Algae on filter pad???

[FishieKeeper429]

So I haven't been good at cleaning my tanks but one thing has shocked me, when I was about to clean out my tank my filter pad was a gross brown and had bright green "stuff" on it. Is it algae and is it bad?? Thanks.

 

[Rivercats]

Is the filter pad exposed to light? True algae needs light to grow. Do you have a picture? Go to this site and did it look like picture number 2, blue-green algae aka cyanobacteria? James' Planted Tank - Algae Guide

 

[FishieKeeper429]

Here's a picture:

 

[Rivercats]

Interesting! Is the filter top open like that all the time? I've never seen algae growing in a filter like that before. I'd say the brown gunk is just detris build up and it appears algae has just grown on top of it.