NANFA-L-- silica = diatoms?

Mysteryman (bestfish at
Sat, 22 Oct 2005 08:18:34 -0700

Some nitwit on some forum tried to start a flamewar with me regarding
the relationship between silicate & brown diatom algae.
I tried to ignore him, but he wouldn't be unheard, and eventually things
got nasty, as they tend to do on such fishboards.

The trouble started when a novice asked about substrate in a reef tank.

One of us suggested that he avoid silica beach sand in order to avoid a
dense diatom bloom which would virtually turn his whole tank brown for
months, and suggested aragonite sand intead not only to avoid this, but
for it's other benefits as well such as buffering and invertebrate growth.

The other one of us said that that's just a myth, that silica does not
enourage the growth of diatoms, and that it it did we'd all have huge
problems since glass is made of sand, and that we should instead dose
our tanks regularly with silicate if we don't have a silica substrate
for the benefit of invertebrate growth.

Each of us thought the other a complete moron, and a fight ensued after
the original questioner asked us to convince him which way to go with
his tank, since he figured that at least one of us was obviously very wrong.

I won't say which guy was me so as to not influence your answers, but
what do you think? Does brown diatom "algae" become more problematic in
a tank with a silica sand substrate? Given a choice of silica &
non-silica calcareous sand, which would you choose?

The thing is, his arguments blindsided me with some goofy so-called
facts of which I had never before heard and couldn't counter, and I got
soundly defeated. Even worse, this jerkwad is one of the popular people
of that forum, and I wound up having to leave. I guess that bugs me, but
not so much as the possibility that I was right along, or, worse, wrong.
I figure you guys make up one of the smartest assemblages of fish people
on the internet, so it seems to me that you'd make the perfect panel for
discussing this.
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