Unless they are a bonded pr, firefish are best kept singly.
Canthigaster puffers can nip clam mantles.
Flame scallops need to be fed filter feeder foods, and often position themselves deep in the rocks.
Personally I feel a purple tang will be fine in a 90g, but kole and tomini tangs are smaller.
If you don't have any other pod hunting fish, after six months your tank should be able to produce enough pods on it's own to support a mandarin without having to supplement them, especially if you have chaeto somewhere.
If you are interested in wrasses, look into fairy or flasher weasses. They don't hunt pods.
Canthigaster puffers can nip clam mantles.
Flame scallops need to be fed filter feeder foods, and often position themselves deep in the rocks.
Personally I feel a purple tang will be fine in a 90g, but kole and tomini tangs are smaller.
If you don't have any other pod hunting fish, after six months your tank should be able to produce enough pods on it's own to support a mandarin without having to supplement them, especially if you have chaeto somewhere.
If you are interested in wrasses, look into fairy or flasher weasses. They don't hunt pods.