Mantis Diet

[Limbo]

I've an N. Wenn and try to feed it regularly via a feeding stick (chop stick with extra pointy end) a mix of frozen raw shrimp, squid and octopus. I try to keep an Emerald in the tank with him, sometimes they last weeks, sometimes days. If it's weeks he gets an new playmate, otherwise he waits. Too expensive otherwise. I also have hermits for him to munch, but he doesn't take them very often. He very rarely gets a small chunk of frozen Formula 1.

My questions :
Is this an ok diet?
Am I missing anything?
How do I know if I'm underfeeding, or overfeeding?

The tank params are always fine so guessing not overfeeding. However, when he arrived as a hitchhiker he was a glorious red. Now he is kind of faded and looks almost the same as the coraline in the tank. Could be food, lighting, change of environment or just one of those things. Being my first Mantis I have nothing to compare my experiences to. You guys on the other hand have plenty of experience and I'm hoping you'll once again share it with me

He's been a happy looking Mantis for 9 months now.

[dc]

I believe they change color to blend into their surroundings. Mine has also darkened up. I keep snails and hermits in with mine for snacks. It will eat about anything I put in. I think variety is probably a good thing. I do put Zoe and Selcon on my food. I feed, krill, pe mysis, and prime reef. I feed every other day. I want to make sure it is eating the food and not hording it.