I have my black ghost and he is blind. Granted he has "sonar" or whatever, and he will get to swimming so fask that he bumps the sides of the tank, but has never been hurt. I have to be extra careful too cause he doesn't have any scales and will cut easily. I sanded down all over his houses and only have soft plants in there for him. Sure, his houses look like they're worn down, but hey, it's "rustic" lol! I have taught him to come right up to the surface while I use the kitten feeder and he takes the food right out of the end, SO FUN! I squirt a little of the blood out first so he knows that I am there. (Have no waste that way either). I have only had him for 2 1/2 wks. I am also training my dwarf gouramis to do the same thing and so far it is working out well! The only ones I can't get to do it are the loaches, they are a little too crazy! I think they have ADD.....lol. I'll bet you could train a blind fish the same thing!