The Banded Coral Shrimp... Doesn't need to be introduced since it is recognized as easily as Ocellaris Clownfish. They are interesting lively - characters - with a refreshing personality... And not as easily mated as you think !! Females become much larger than males and can eliminate an unwanted partner... It is best to get a pair that formed a couple as juveniles. They require large tanks that are well stocked with a natural variety of invertebrates to consume... (something rarely found in Sterile Tanks). Nevertheless they will consume just about anything thrown in the tank... But as a veterinary friend once joked about: it's not because they're crazy about some meal that's it's necessarily good for them !!! Distinguishing sexes is quite easy: view the specimen - from above - if it shows a turquoise or light green area on it's back: these are the female gonads !!
Same as Lysmata Amboisensis: only one pair can be maintained in one tank !! Cleaner shrimp can be placed in a tank by the dozens: LOL - it doesn't mean they will all remain there after several months !! The Dominant Couple slowly eliminates any competition !! And though it's rarely mentioned: Stenopus Hispidus are cleaner shrimp also; although they perform this action in the wild on large specimens mostly... Some fish species simply can't be trusted with shrimp in the long run: Premnas Biaculeatus is a perfect example, capable of also eliminating any fish they find unsuitable as company !!
If you've never witnessed an invertebrate's molt (crabs, shrimps, amphipods, etc)... Think of a fighter jet's ejection seat: the canopy blasts open and the specimen is propelled outside. After ejecting themselves from their exoskeleton they will remain motionless for several hours until their new armor hardens.
You should always leave the shedded exoskeletons of Crustaceans in the tank !!! They consist mostly of CHITIN. Crustaceans need to replenish on it for ulterior molts. They will eat them to do so and that of other species in most cases. Chitin can also be found on Mussels (protective coating of outer shell... chitin also forms the nails on your fingers...)
STENOPUS nibbling on Platyhelminthes (Red Planary Worms) Luckily for it these are not toxic... However most Flat Worms are HYPER-INVASIVE and carry potent toxins !! They simply ruin the show for any Aquarist !! And don't expect any marine species to rid the tank even if they eat a lot of them...
Red Planary Worms should be eradicated from ANY Aquarium
They will invade the tank as badly as Aiptasia Parasite Anemones !!
They can attach or adhere to just about anything. Such as fish fins or gills; algae; rocks; other invertebrates; etc...
They can also be found free floating in the water. They can travel easily from tank to tank... from plastic bags to other destinations....
Stenopus has expertly extracted a prized meal from a crevice: a Polychaete Annelid Bristleworm
She quickly returned to her lair under the rockwork to enjoy the delicacy calmly. It is savoured by countless fish species... A Marine tank without them is missing something very important !!
Keep in mind that bad molts (missing limbs) with crustaceans are not always because of bad nutrition or water chemistry... As I mentioned above: CHITIN is vital to their good condition.