Originally Posted by
caj
According to Wikipedia:
Although Aquaman can remain underwater indefinitely without suffering any ill effects, he grows weak if he remains on land for extended periods. However, when Batman invented Aquaman's water suit he was able to walk on land for an indefinite amount of time and was no longer vulnerable to a "dehumidifier". This weakness was later removed from continuity in 2011, establishing that he grew up on land before learning of his Atlantean heritage, but he still runs the risk of dying by dehydration within incredibly hostile environments. Aquaman had also been bestowed an ability he never showcased before, given to him by an old Sea Monarch, granting him the ability of unaided flight using his own power.