The System is located as Headstone of the Glittering Tiara. Aquaria is most notable that it only has one very small chain of Islands near the Equator. These Islands are covered with steaming Jungles were hardy colored Junglefighters dwell. The northern most Island is covered with the Grandcity of Semam the principal Spaceport. The southernmost island is home to Codex Chapter of the Aquamarines, descendants of the Ultramarines. 95% of the population thus live underwater in huge Aquahives deep down on the Oceanfloor.
One of the hive even covers the interior of a great rift chasm. Because of the habitation constraints of the aqua hives many young join the Imperial Guard making Aquaria one of the few planets constantly raising regiments. These “Hiver” regiments get their thorough training by the trials of combat. It is not unheard that by this two or three regiments are combined to form a new one because of initial losses. Regimental numbers are constantly reassigned.