I feed my clowns and all my other fish a mixture of flake and brine, alternating every other day and a tiny sprinkle of flake of an evening.
Haven't tried mysis personally but my clowns will eat anything I put in there. Including fingers! Lol
if after 24 hours they still refuse, try live brine from your LFS. even the most stubborn clowns cant resist live. then gradualy move them to frozen brine and then mysis
Think i got them beat with D and D reef paste at least the little one is nibbling it. The larger/ possible female is being more stubborn but no shock there
Just like to quickly say the people at South West Marines where excellent. Pleasant and extremely helpful. Especially as the clowns weren't even purchased there.