"HTH" wrote in message
...
I would be more worried about it killing fish.

Go to the crafts section and pick up some of the polyester batting used to
make quilts. The brand I have been using is Create-A-Craft. Most possibly
from Wally WORLD.

HTH

Heather wrote:

I picked up a white filter product intended for furnaces that looks a little
like quilt batting. However it says on the package that it has been treated
with a microbial to inhibit microbe growth. Since I wanted to put it at the
top of my lava filter I am concerned that it will kill the beneficial
bacteria there. If I wash it will that help or should I just forget it?

Thanks,
Heather

Most likely it won't kill the fish. However, if you are trying to use if for
mechanical and biological filtration, it certainly will not allow the bacteria
to colonize in it. I wouldn't use it.