In my experience, inbreeding doesn't seem to bother fish very much. Certainly you don't want it to happen too much, but I have several species of fish that have inbred and they look fantastic. I'm sure if I continued this line with absolutely no introduction of new genetics, some problems could arise... But after a few generations, they're doing great.

I will add new genetics to the line soon, for what it's worth. It isn't an experiment to see what will happen. In most cases I never expected them to breed to begin with.