For some reason or another, the image I get of "substrate appression" is of
a filthy peasant, lying in the "substrate" before a King, in a certain
British comedic movie, arguing socioeconimics and yelling "I'm being
{appressed}! Can't you see he's {appressing} me!" :)
>Perhaps they are selecting alternate foods - meiofauna in the sand, etc.
That's the thing though. They perform _this_ behavior when they're not
being fed, or haven't been fed. They route right through, sift it, and then
spit the sand out through the gills and the mouth when they exhibit this
behavior. It's more like a vaccum-cleaner-like behavior, and it's quite
distinct. They do this a lot on the days where I fast them. You can always
tell those days, because there's loose sand _everywhere_ (they disrupt the
biofilms that normally hold it in place)
But this is totally different. They have been chewing on a mouthful of meat
for 30 or so seconds, and then dive into the sand, take a big divot, which
only the larger granules come back out, with a small amount (in comparison
to the bite) of smaller granules.
While I think it's _very_ obvious that the sand is multipurpose... I'm
still voting for "gizzard" in this specific behavior like I had initially
guessed at, and Bob also suggested. It will definately be interesting to
get ahold of the work from people who've also spent a good deal of time
watching this. Other species would be great too... The spotted sucker
exhibited the same behavior last night. I just need to get to school so I
can designate time to look all this up for myself. Or even find some space
to set up a rack of tanks with different substrates and see what happens ;)
In any case... Start maturing those live sand beds (I'd do 6 months minimum
before introduction) and enjoy yourself some suckers!
Todd
It's never too late to have a happy childhood.
http://www.farmertodd.com
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