My Bolivian never left the lower half of the tank. I never saw him even approach the upper level much less the surface...except the time he was "organizing" the Bleeding Hearts! But both species are substrate feeders, though that does not mean they may not surface feed. The genus name is a clue to this, derived from the Greek mikr [= small], geo [= earth] and phag [= eat], literally "small eartheater."
