PlanetCatfish.com

I recently obtained a couple of what I think are juvenile M.cavasius. These went into a tank already housing a trio of M.tengara. The "cavasius" immediately(and very agressively) evicted the tengara from their pipes/tiles. The tengara then moved to the rear corner of the tank furthest from the cavasius and excavated a depression in the sand substrate(2"), the excavated sand was thrown around the depression forming a sort of wall.
The tengara have resided there ever since(1 week), only coming out to feed. anyone else seen such behaviour?

<i>Mystus</i> of the <i>M. cavasius</i> group (what Tyson Roberts calls <i>Mystus</i> sensu stricto are among the most aggressive of <i>Mystus</i>. I have kept a <i>M. singaringan</i> (which looks almost like <i>M. cavasius</i>, except for lacking a spot at the base of the dorsal spine), and it was very aggressive towards tankmates. Eventually, I made the mistake of housing it with a <i>Hemibagrus</i>, and the <i>Hemibagrus</i> killed the <i>Mystus</i> within 15 minutes.
I have seen <i>Mystus</i> dig around like that, mostly when cover is absent.