Just wondering if any one has any experiance with these fish , thinking of setting up a fish only tank with one of these with a regal and porcupine puffer. The tank will be 55 gallon ( I know to small for a regal , she came off a friend who won't put her back in his tank due to ich issues )...

my blue linckia has been doing great. and is still moving around the tank happily. the other day i noticed a few spots that looked ripped on one leg. the next day (2 two) it seemed to be gone. I now see one again. any idea what this is or how it happened? i wondered if it was a rock or maybe a...