Coladrium flow was a type of energy used to replenish fuel that was employed on vessels used by the Tosk in the 24th century. In 2369, Tosk explained to Miles O'Brien that the coladrium flow converted space energy into fuel and sent it to the ship's arva nodes. It functioned in much the same way as ramscoops on Starfleet vessels. (DS9: "Captive Pursuit")