Shrimp, hikari food sticks, krill centipedes, frogs, turtle and centipedes. Most of it has to do its genetics. Water quality and a good diet helps too. Alot of people use tanning lights to get the deep red
Not too many of the lfs carry Asian aros here in Vancouver. Alot of the owners say to make a group order for a shipment from one of the vendors/ farms. Or you can look in the marketplace for someone selling a grown one
I doubt you can get that level of red with any aro, regardless of genetics or diet, without using "trick" lighting. Just google "nan light", or look at this clip, you can see the red colour from the light on the normally white bits of the dat; http://www.youtube.com/watch?v=bokxM0uaTxQ