My clowns eat any thing I give them they were picky when I first got them but now they eat like pigs. Your clowns will eat if they are hungry and if they still don't eat they may have a parisite you could see if a fresh water dip gets them to purk up a bit.
If it does then you may have a parisite or some thing else afecting them. Are there gill plates flared out? This could indicate a parisite that resides in the gills.

Just sit there and watch them for a bit for head shaking, mouth puckering, flared gill plates,realy red gills.

Let us know what you see and try and post a pic of them.
Bill