New to reef aquarium

[kitt808]

I'm new to the saltwater aquarium. I started two months ago with 40 gallon tank, cycled the tank for 6 weeks. I introduced some clean up crew with 2 cleaner shrimps, 3 hermit crabs. How many cleaner shrimps can I have in the tank?

 

[Sniperhank]

I'd stick with that many. They are peaceful, but I'm not sure if they'd become territorial or not.