plants also and very little in open water. Constant up and down swimming against glass side of aquarium - gravel, then surface; gravel, then surface (most of the time - although the fish go to the surface - do not touch surface with mouth - not feeding or gulping air). One fish observed in center of aquarium (open water). He swims slowly around in a large circle, keeping fairly level. No territoriality observed. 28 September 0930hrs - Fish quite inactive - one fish is continually going up and down against the face of the aquarium - each time apparently nipping at the bubbles floating at the surface of the water. Once the fish (~13mm) swam under a plant leaf and it interrupted his ascent - the descent followed (without going to the surface). Other fish on gravel bottom. Some movement, but nearly always for a very short distance only. ~7 times (swim across center line) including one fish probing in the center area, and crossing 3 times (4 fish in the 7 times) Turned on light in aquarium - movement even of the fish continuously