Is it possible you're thinking of Code Lyoko? It involves teenagers fighting monsters in special zones, and there are a few reporters who show up as characters.
Jeremie Belpois, a 13-year-old boy attending boarding school at Kadic Academy, discovers a quantum supercomputer in an abandoned factory near his school. Upon activating it, he discovers a virtual world called Lyoko with a young girl, Aelita, trapped inside it. A series of bizarre events begin to occur at Kadic Academy. Jeremie learns of XANA, a malevolent artificial intelligence/multi-agent system who also dwells within the supercomputer. XANA's goal is to conquer the real world and all human beings.
Throughout Season 1, Jeremie works to materialize Aelita into the real world and stop XANA. Jeremie is aided by his three friends Odd Della Robbia, Ulrich Stern, and Yumi Ishiyama as they are virtualized into Lyoko in order to save both worlds from the sinister virtual entity alongside Aelita. In "Code: Earth," Aelita is finally materialized, but the group discovers that XANA had planted a virus inside Aelita, which prevents them from shutting down the supercomputer.
The second season focuses on the group as Aelita adjusts to life in the real world while Jeremie searches for an anti-virus for Aelita. In Lyoko, a fifth sector is discovered and the group explores more of Lyoko's secrets and mysteries, while XANA attempts to steal Aelita's memory in order to gain the Keys to Lyoko and free itself. At the end of the season, Aelita and Jeremie discover that Aelita does not have a virus, and instead is missing a fragment of hers. XANA tricks them with a fake fragment and succeeds in stealing Aelita's memory and getting itself out of the supercomputer.
In the third season, XANA destroys each of Lyoko's surface sectors one by one, until only Carthage, the fifth sector, is left. The group invites William as a member, but upon being virtualized, he is possessed by XANA. Shortly after, he destroys the Core of Lyoko, rendering the group helpless against XANA. After what they thought was their defeat, Jeremie receives a coded message from Franz Hopper, Aelita's father, that allows him to recreate Lyoko and continue the fight against XANA.
At the beginning of the fourth season, the group builds a digital submarine, the Skidbladnir, to travel across the Digital Sea to destroy XANA's Replikas, which are copies of Lyoko's sectors that are linked to XANA-controlled supercomputers on Earth. XANA uses William as its general throughout the season to defend the Replikas. Near the end of the season, XANA decides to gather energy from hundreds of his Replikas to create the Kolossus, a seemingly invincible monster that later destroys the Skidbladnir. Before it is destroyed, the group saves William from XANA's clutches. After he returned, he had a difficult time gaining the trust of the Lyoko Warriors. In Code Lyoko: Evolution he was referred to as a permanent addition to the group for the first time. While Ulrich defeats the Kolossus, Franz Hopper sacrifices himself in order to power Jeremie's "anti-XANA program," which destroys XANA upon activation.
I don't think they really do space, but Nav Skids are used to traverse the Digital Sea, which kind of fits with you thinking of it being both space and the water.