unknown growth in over flow

[dottiede]

Can anyone identify what is growing in my overflow? this is the large one and it looks like there might be 3 more smaller ones.

 

[Roosterjack]

Cool looking. Following.

 

[Brit’s Fish]

It’s a sponge! They’re good filter feeders and shouldn’t bother anything in your tank.

 

[Billdogg]

It’s a sponge! They’re good filter feeders and shouldn’t bother anything in your tank.

^^^This^^^

Just a good sign of a healthy system.