hehe the halichoeres is proven to wack pyramid snail.... as for the nudi i was looking for a wrasse that wack the nudi(in RC thread there was a pic of this wrasse), can't find it... Got this, I spotted a nudi on my glass yesterday try to catch it but it flew lose, and i was thinking oh no, if this guy stay in my tank i gotta be in some trouble... out of the blue my zigzag wrasse just wack it and then into its stomach
now for your fish that eat cyano., none that i really know.. but I do know 2 spot goby keeps sandbed super clean... you may want t try those but they are not easy to keep... my fren tried a pair and the cyano and diatom just disappear..... I guess small amt of cyano will but i not sure how much red carpet you have lolx