"Carola / Les" wrote in message
. ..
We are all familiar with the 'good' bacteria that we try to cultivate in
filters and gravel etc. but where do the 'bad' bacteria lurk ?
How do we distinguish between 'good' and 'bad'?
Are they in the dead algae that is killed off by the uv light which then
appears to accumulate on the rocks and bottom ?
Is that the black slime that appears on the rocks?
How do we get rid of the 'bad' boys ?

The good stuff has halo's and wheres's white robes. You'll find the bad
stuff in the corner of the pond, smoking, drinking and making lewd comments
to your koi.

BV.

Sorry...couldn't resist...