Question about bio-wheels...

[Udder Juice]

So, I've never really had an aquarium with a bio-wheel before. I understand how it works but my question is, what is it supposed to look like once its cycled properly and has a culture growing on it. This tank has been running for four months now and the fins on the bio-wheel look just like they did when it was new. I would expect to see something growing on the fabric surface.

It spins pretty fast, is this preventing a proper culture from taking hold?

Thanks for any info.

 

[reefdiver]

You won't see anything, over time they will turn darker.

 

[Lt.]

I have a penguin 350, it looks kinda dark brown, green, given its been like a year or more.

 

[dmolavi]

They don't really add much in terms of bio filtration:

Do Bio Wheels really work? Bio-Wheel Review