Im not sure about the two diferent types of peppermint shrimps, however i do know that not all peppermint shrimp eat
aiptasia's. if you would like to try cutting the
aiptasia's down alittle that might give them more motivation to eating the pests. Once the
aiptasias get to be a certain size peppermint shrimps dont really go after them. Even with cutting them down there is a still a chance the peppermint shrimp might not go after them. My suggestion for a 100% death rate with the
aiptasia is to dose them with a needled syringe untill they are gone. wish i could help you more..