Yea that looks nice & healthy. I have seen them catch food from the current too, but IMO this is a species that should definitely be target fed meaty food. In the long run I don't think they will thrive just catching random particles. It's fun to watch as well. I've found the short tentacled variety to be very hardy, but I did lose a long tentacled plate once and haven't tried another.
Good luck with yours.