Thank you both. Your threads have me some knowledge on their care. Do you recommend a dark background to decrease their tendency of running into the wall?
In general I think fish do better in ponds than in transparent tanks but since we need to see them at least one side should be transparent. For skittish fish it should make more of a difference. In general.
IME, yellowcheeks don't run into walls, at least not in the lethal fashion the ATF do, not as much or not at all, but they do earnestly try to swim through / against the walls head first and at length in an attempt to swim away from perceived danger and as a result they rub bad sores on their snouts. I believe they won't do it or would do it less if a wall was not transparent. Better yet, far, far better yet, is to give them ample swimming room. Hence my advice above citing the unusually large space requirement.
Don’t know if there’s a correlation between lighter backgrounds and skittishness of fish... my guy was in a dark background tank and was still pretty skittish. Do you mind posting some pics of your fish and a full tank shot?
Agreed, the innate skittishness may not be alleviated (but the behavioral could be) but the question here is about the consequences of it, that is the darting, the swimming away, or other avoidance of perceived danger, I think.