How long have they had it would be my main question. That looks like a Haddoni to me, freaking gorgeous!
Those need very strong lighting and from what I've read tend to grab fish a little more than a gigantea/true carpet. I've heard once they are established they are pretty hardy. If it's established pull the trigger, they are prone to infections during transport so if it hasn't been there a few months be ready with some cipro and a QT tank.