Y'know. . . I really DO think Sparky is a girl... I randomly read info on electric catfish, and keep running into the information that MALES are more SLENDER. Slender... our Sparky is not. Of course, this IS in comparison, and so I suppose we're no more ahead than we were before without a pair!
Sometimes when Sparky swims up the glass with his stomach showing to me, I sorta . . . look. But I can't tell. At one point, I thought for sure he was a male but the next time, I wasn't so sure. Sorry for invading your privacy, Sparky!
Do the cat try ot get at the tank on the floor? My cat drank from my fish tank when I had it off to change the filter. And she used to sleep on it. Thats the only time I really get mad at her . . . then give her the cold shoulder for a bit. Little rodent. :p