Totally read this as leg spread on a 29g

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My Radion is over a 24" tank but its a little lower than it should be, the intensity never hits more than 60% so I would say hanging it a little higher on a 30" and increasing the intensity would work just fine.
My guess is a juvi orange shoulder tang, hard to tell when their small though and keep in mind there are hybrids of orange shoulders and Lieutenant tangs so you never know.