Re: NANFA-L-- Tiny limpets(?)-in-water line / snails & crayfish

Laura Burbage (
Thu, 1 Dec 2005 12:12:51 -0800 (PST)

Hi Jase,

Crayfish are good about eating/shredding just about
any plant. However, you may also find that
Ceratophyllum just doesn't want to stay anchored. The
lower, older segments die off as it grows. You can
keep trimming and re-anchoring it, but most people
don't bother and just let it float around.


Date: Thu, 01 Dec 2005 00:28:31 -0500
From: Jase Roberts <>
Subject: NANFA-L-- Tiny limpets(?)-in-water line /
snails & crayfish


In one of my native tanks (north-central Vermont) I
started seeing tiny
snail-like critters right about-in-the water line.
These guys are
really small -- from less than 1mm long to maybe 2mm
long now (definitely
growing somewhat). I can't make out too many details
with a 10x hand
lens, but I can see that they've got snail-like mouths
and probably
antennae. What I can see of the shells looks a lot
more like a limpet than
a normal snail. They look to be roughly conical and
fit tightly to the
sides (I can push the critters around with a toothpick
and they stay
suctioned to the glass). The top set of pics-in-the
bottom of looks
about right,
although mine are way smaller. There are probably 15
or so visible in my 10
gallon now, all right-in-the water line.

Do folks have experience with freshwater limpets? Are
they common
thing to have living in native aquaria? Any chance
this is actually a life
stage of a more conventional snail (I did have some in
snails in this
tank earlier)? I'm surprised that there doesn't seem
to be anything in
the NANFA e-mail archive mentioning limpets.

Second, I'm wondering about folks' experiences with
interactions. I had 6 or so smallish snails in my 30
gallon tank that
disappeared within a week (only one large ram's horn
snail remains). At
the time I blamed my pumpkinseed, but now I wonder if
the crayfish I had
was actually the guilty party? I see some references
to crayfish
eating snails elsewhere on the Internet. Is it
possible to have snails and
crayfish co-exist in a tank, or will crayfish
eventually wipe the
snails out? I feel like I need some snails to control
algae growth.

I also suspect my crayfish to be the culprit in
cutting free the
Coontail/Hornwort (Ceratophyllum) plants I have tied
to rocks-in-the bottom.
The plants are doing great in my 10 gallon tank
without crayfish, but
most were floating free and stuck to the filter within
a week or two in
the 30 gallon where the crayfish lives. Again, do
other folks have
experience with this? Solutions to keep the plants in
place? Sorry, no
idea on the species of the crayfish.

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