CBS pose NO threat to stomatopods (except during the stomatopods molt cycle)....from personal experience, the CBS's are not called boxing Shrimp for no reason, they will fight any other shrimp in the tank :) except mantis .. now thats a fight i'd like to see :)
Where do/can you buy live stock online in Aus ?Just get some peppys online, they travel really well when packed properly.
Do you find the Redlines territorial as well? Mine tends to have a favourite area in the tank but is away from where the peppys are...In fact the peppys live under the same rock as that red and white crab of mine. I tend to have one peppy that's bolder than the other one...the big one is quite elusive actually and you don't see it much at all. I often wonder if it is still there until after a month or so they both turn up together.I have a pair of CBS in my large display tank. Also in this tank is about 20 pepermints. I have not noticed that the CBS are an issue with the peps as the peps move quickly when compared to the CBS. Also the peps will get into the narrow gaps in the live rock, gaps where the CBS cannot fit.
If you want to keep peps wit the CBS, ensure the tank is large enough, and there is enough rockwork with suitable gaps for the shrimp to avoid each other. The CBS set up a terretory (cleaning station) which they defend. They exclude the other shrimp from this area.