Should have posted this earlier ...
One of my remaining WCCMs had been swimming poorly for a month or so, and tending to swim to the left. Seemed also a bit large so I wondered if she were a female with eggs ( a fry appeared in the tank a month back ) No external signs of disease and ammonia levels undetectable.
Came back from conference on Sunday to find her at the bottom of the tank ( 50 cm deep ) lying there just rapidly breathing. And just occasionally swimming up a little before dropping back.
Since there is no current in this tank, and she was lying at the bottom of the wrong side of the Hamburg mat filter, I managed to get her into a floating breeder trap on the other side of the filter hoping to get higher O2 levels. However, the angels there must have spooked her and she did a jump landing into the bottom of the tank where I can not easily reach her. Unexpectedly she is still alive but not moving. Tank is set at 23 deg C.
Any suggestions?