I don't know, I think certain species of octopus and seahorses may be able to go together. Do any of you really know for sure?? Or do you just enjoy being closed minded? I got the exact same response when I inquired about seahorses and other predators
but.... 
Dwarf octopuses are nocturnal and prey on mollusks and crustaceans and stay small at a size around 4". Somehow I don't see such a creature going after a full grown seahorse. I don't know for sure but at least I'm making that clear.