The Flash uncovers one of Aquaman's best-kept secrets in Voidsong #2

gamesradar.com:

Superheroes have conflicting goals all the time, but when those heroes are friends – like Aquaman and the Flash – feelings can easily get hurt even in the midst of huge battles. 

Written by Collin Kelly and Jackson Lanzing, illustrated by Vasco Georgiev, colored by Rain Beredo, and lettered by Troy Peteri, Aquaman and The Flash: Voidsong #2 follows Arthur Curry and Barry Allen as they attempt to hold out against the alien invasion of the Voidsong, which has already claimed everyone else on Earth – including the citizens of Atlantis.

Using one of the high-tech computers in Atlantis, Barry determines that the aliens are actually eating Earth's kinetic energy, which explains why everything has essentially come to a halt – the people, the rain, everything. He also tells Arthur that the Speed Force manifests as kinetic energy in this reality.

Together, the pair board the alien ship with a plan to destroy the Voidsong technology from the inside out. Once onboard, Barry has another, more frightening realization: These aliens hunt and eat the Speed Force itself.

But oddly enough, the ship doesn't seem overly eager to consume Barry, despite the fact that he literally lives and breathes the Speed Force. 

The ship wants Atlantis because for decades, Arthur and his wife, Mera, have been working on a program to take the Atlanteans to space, and they've been using the Speed Force as fuel because it doesn't burn. 

Barry is of course horrified, and he also feels betrayed. Arthur used his access as a Justice League member to study the Speed Force through the group's documentation of it, and never once said anything to his teammates. 

Worse, he never said anything to his friends. And when Arthur argues that he and Barry weren't friends