Mold growing in my filter

[Cassandra90]

I notice that my water bottle baffle had mold in it so I took that apart and then notice it was coming from the filter. So I shut the filter off and I wipped the mold off. I don't wanna replace the cartridge sine the beneficial bacteria. What could the mold be a sign off? The tank is about 2 months old. I cycled it for a month. I did have a problem of foggy water. Other than that the parameters of the water are all where it should be the water is crustal clear, I do 50% water changes weekly and a 10% water change mid week. It is a ten gallon with a divider.

[Oldfishlady]

Can you post a clear pic...are you sure it is mold and not algae or BGA?

[Cassandra90]

Well I whipped all the mold off. It was more like solid gray mush stuff. If it comes back I'll for sure post a pic.

[Cassandra90]

It didn't spell terrible but it was like a earthy smell but not a good earthy smell. I was able to stand the smell.

[Cassandra90]

Here is a photo I found on google, but it is in my filter and it is a bit darker like a gray.