It usually takes a while to get them eating frozen.As far an other inhabitants they should always be kept alone since they can eat fish the same size as they are in one gulp. A feeding stick is almost always needed since they are ambush predators and use their lure to trick fish into getting close to its mouth since they are extremely slow. I honestly doubt just dumping frozen food in the tank will get any type of feeding response.Good news is you only feed them once a week so its not a real big deal.
Feed your Filtration
Give it to Porc Chop he'll eat anything!!!!!
"This is my tank and these other fish just live in it"
^ Quoted from Porc Chop^