just take your finger and wipe across the heads you wont get brown algae off with a baster, problem is they have closed and either now have algae on the face or closed and know algae is on the heads.if it was cyano you could blast it off but brown algae is basically the film algae on your glass and youll need to wipe it away gently.problem could be many but i would guess phosphates and direct light which is prime breeding grounds for algae.if your zoas are still small and not grown in or on you can move them to somewhere where light isnt as intense.either way you wont be rid of it untill you control your phosphates and thats also assuming your nitrates are very low or nil.
its a problem alot of people face with zoas and the answer is not getting the algae off its keeping it off the more you ignore the phosphates the more it grows back once it stops they will open again in no time.if they were dead the mat would quickly melt away or they would float off and melt.
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