Re: Antibiotics for cyanobacteria

>        I recently treated my tank with 2.5mg/l of erythromycin to get
>rid of some cyanobacteria that were beginning to grow over my lileopsis.
>The treatment worked for a majority of the bacteria, but there are still
>a couple of small patches left after 4 days. Are there any other
>antibiotics that can be used against Gram negative bacteria that
>will not damage the plants or cause any other excessive harm? What I am
>really asking is whether anyone else has tried other antibiotics in a
>plant tank with better success rates. Thanks.

The rest should die off with a full treatment--see the instructions on the box.

BTW, the treatment did do a number on my biofilter. (I can't tell whether
it was the antibiotic or the die-off that may have overloaded the
biofilter.) Specifically, the bacteria that converts nitrites to nitrates
was killed off.  I kept testing for ammonia and nitrates, found zero of
both, and thought all was well. Only after my fish started showing symptoms
of illness did I test for nitrites and found a spike through the roof.

Greg. Tong
San Francisco, CA, USA
gtong at sirius_com

"Every infinity is composed of only two halves."