I have a male vieja synspilum who is currently 13", I've had him for almost 3 years and in the last 8 months or so I have had 3 different females ranging in size from 4 to 8 inches. I can't seem to find a successful partner. The current female is only 4" and spawns all the time with him barely taking notice. What should I do, could he be sterile? Maybe I haven't found the right female yet? Can anyone help...because I really love this fish...what should I do?