Both mandarins and scooter blennies eat pods
. They are both dragonets, look them up on liveaquaria, they're in the same section.
you supplied for the tank won't last long, with 2 pod-eating fish in a tank that size they'll be gone very soon. IMO
both of those fish shouldn't be in tanks that small, regardless ORA or not. One day they might just stop eating prepared and you won't be able to add pods
fast enough for them to eat (they literally eat constantly)
But if you saw your mandarin eat prepared I suggest you do that every other day, and attempt to feed the scooter too, they are more easily trained onto prepared than mandarins, but still difficult.
Once you see the bellies cave in it's too late, maybe bring them back to the LFS
before that happens and all you can do is watch them starve.