Wow! That is a gorgeous lyretail. Mine is still more pinkish than red, but I think it's because he is only 2 1/2" or so. I'm hoping that since he has full male coloration so small that it will only get more intense as he grows.
I feed a homemade frozen food mix. My lyretails eat it enthusiastically. I occasionally will give an extra feeding of marine flake and they will eat it with a lot of catching and releasing before they actually swallow it.
When I first got them they prefered plankton(largest particle) mysis(med) or spirulina enriched brineshrimp(smallest). The problem I had with the frozen whole foods was that they never seemed to like the same size 2 days in a row so it was a constant guessing game if they would eat what I was putting in the tank, so I made a concerted effort to get them to accept the frozen mix.
I started with two females. I started with live brine for the first couple days, then started mixing frozen brine/mysis. By the second week I was able to feed all frozen brine/mysis. A believe it took about a month and they started eatting the Hykiri S Pellets and Flakes (Prime Reef & Forumla 1). Now, after 1-1/2 years, they basically will eat anything I put in.
The single male I used to have was a little more fussy. It took me 2 - 3 weeks to wean him off the live stuff and he didn't touch flakes until about 6 months. But then he eventually started to eat everything. HTH
When I first got mine they wouldn't eat. They would mouth the food and spit it out. I tries feeding them all the good stuff (mysis, mini-mysis, marine cuisine, rod's food, H20 life frozen) and they wouldn't eat. I tossed some spectrum pellets in a few days later and they ate them like they were little fish skittles. After they ate that for awhile they strating eating everything.
So I don't know if they actually liked the pellets more or it just took them a few days to eat.
Well, I had mixed results this AM. I saw a lot of "spitting" as a response to the mysis. I saw a bit of interest in the flake. The male tried some of the Nori, tasting, spitting, chasing, tasting again. I am off to the LFS for some more variety.