Bio-wheel question...

[vaheelsfan]

I purchased a biowheel filter to put on an already cycled tank five days ago. It's running fine, and the wheel is turning, but the wheel looks the same as it did when I bought it. I thought it was supposed to "change colors" signifying the growth of bacteria? Is it good or bad that it hasn't changed?

[JSchmidt]

It will take several weeks to darken. Maybe longer if the tank's bioload is light. I'd give it at least 2-3 weeks.

HTH,
Jim

[often dignified]

I've had mine for nearly 2 months (Penguin 125 on a 10 gallon) and it is just now starting to darken. I've had a very small bio load though. I think I read somewhere that there is close to 900(? don't quote me on it... but I know it was a high number) miles of thread on those bio wheels, so just because it isn't dark... that doesn't mean there isn't bacteria on it.