im 0 for 4 on keeping royal gramma

[hotelbravo]

Yes the marine betta and the 3rd gramma were introduced at the same time and the marine betta is doing great

 

[ThRoewer]

Bristle worms aren't predators. They are harmless detritivores. They may bother or cause harm to a fish if they come in contact but they certainly are not a predator. There are plenty of predatory worms out there and these should not be lumped in with them.

The small bristle worms yes. But there are some that are very effective predators (though mostly on inverts).
I had some of those that have 3 needle like "teeth" around their moth and one even bit me when I caught it. They are really nasty.