Keeping flagtail with severums?

[terror]

Hi,
wioll it be ok to keep flagtail with juvenile severums?
the flagtail i'm talking about is the silver colored fish with the lips like a kissing gourami? roght no wits my arowanas tankmates. but the arowana is growing quite big and the flagtail might end up as a feeder.
my only spare tank is my juvenile severum tank. would the flagtail be ok with them? the severums are about 2-3 inches.

thanks