"dkat" wrote in
.net:

I don't really know. As I said, it was something I read some previous
summer about the dunks and it convinced me not to use them. However I
can really find nothing useful about it now in the time I think it is
worth investing. I don't know if the story has disappeared because
the original story that I'm referring to did not make the distinction
between the different bacteria strains, if it was based on an in
process study that didn't pan out, if it has just been swept under the
rug because everyone is far more concerned about the diseases passed
by mosquitoes than they are to what may be only a minor impact on the
environment, or what (however I am noticing that being an
environmentalist is about to take the same four letter word status as
liberal how holds).

The one thing that I do know is that I am happy that it motivated me
to get rosie reds and this year guppies. They are far more
entertaining than a floating chunk of dunk. I'm not saying what
people should or should not do.... I'm simply musing on line... I'm
currently having my a$$ chewed off in rec.ponds for similar musings so
I'm getting a bit nervous about doing it at all. DK

Keep in mind, that the mosquito larvae actually have to ingest the
bacteria to be affected. I stuck a dunk in a 5 gallon bucket of water
and after 2 days, most of the larvae are dead, but there as still a few
hanging around. The dunk in question is over a year old and has been
through the mail.

If you've got a rain barrel and it's not raining, it might be better and
cheaper just to introduce a thin layer of oil to the surface of the water
.... kill rate for me was 100% in under a day. Of course, don't use any
oil that you wouldn't eat anyway. For gutters and out of the way
places, the dunks are a better idea.

- Salty