Looks like the ants we get in Texas... The ones that make big hills and hurt like you wouldn't believe. I hate those. They're nasty buggers.
My adventures in keeping Indostomus crocodilus, the crocodile toothpick fish. AKA armored stickleback, paradox fish, and freshwater pipefish. Care is (to the best of my knowledge) exactly the same as Indostomus paradoxus.