TBH and not wanting to sound a complete ars3, but simply don't buy ANY fish you don't know. Always always always research a fish before you buy it. This way you don't end up with a shocker and you'll have happy fish.
I couldn't agree more. i am far more experienced now. (3 years ago i think.) this, and having to euthanise, caused me lots of heartache. i have not fallen into the same trap again.
Research, research, research first three things i, now, do when considering a fish. lol, last, and least important is buying it. unfortunately, even now, most of us start with the purchace.
your point is well taken. unfortunately, i had to learn the hard way.