My choc is a "standard" choc as far as I know but she has been known to change to a very deep red on occasion. But usually she is just your usual choco type colours.
The top pic is from a couple of years ago, the bottom one is quite recent.
My work supervisor gave me 13 golden mystery snails and 3 regular BNP juveniles. The snails are randomly distributed as are the BNP. I added one BNP to the 260 as it has a lot of brown diatom. The female choco was 7ft away when I introduced the BNP to the tank. She was there instantly and had it in her mouth. I figured it was over for the free BNP and was glad I hadn’t purchased it. She spit it out faster than she gobbled it up. It darted away under something and she gave up chasing.