Small But Poignant Tragedy

     Here's something I'll bet no one has had happen before.
     I had a beautiful 15 cm/6 inch Royal Farlowella (best guess I can make 
     is a Sturisoma sp.and not Farlowella) Rather a stout body, so I'm 
     guessing a female; active, voracious and a nice community member.  My 
     tank is heavily planted and I have a Tetra CO2 bell. 
     [for those on the catfish list who don't know what this is, plant 
     enthusiasts often use supplemental carbon dioxide to feed plants; the 
     bell is basically just an inverted cup connected to a CO2 source and 
     therefore filled with CO2, which then dissolves into the water].
     The Sturisoma stuck his head in the CO2 bell and didn't get it out 
     fast enough.  I had the bell close to the sand surface so the the 
     water pressure would dissolve the gas faster, and the fish apparently 
     couldn't back up fast enough to extricate itself in time. It probably 
     was dead in a few seconds.
     This leads to a question:  This fish never was able to navigate 
     through the dense plants well, and looked, well, very clumsy. Does 
     anyone know what type of biome these fish come from?  Do they live in 
     fast currents and not in habitats with a lot of obstacles to navigate 
     through?  Farlowella spp. appear well adapted to hang vertically on 
     plant stems, but the Sturisoma had that lovely high dorsal fin which 
     obviously impeded his/her movements.  
     This fish had wide range of food sources, unlike Farlowellas, which, 
     as I understand it, will only eat soft algae.  I'd like to hear some 
     other folks' experiences with Farlowella, because I've tried keeping 
     them on several occaisions without success.  They live for a week or 
     so then die...I've never seen one try to eat, even though there is 
     enough soft algae to keep a squadron of Otocinclus fat and happy for 
     the last year. My impression is that they don't adapt well, and that 
     if they adapt and figure out how to eat then they are quite robust.
     Bob Hoesch in Ashland, OR, where it is snowing even down here on the 
     valley floor!