A water tank was the name given to a special suit worn by Iskalonians when they left the oceans of Iskalon. The more modern suits were simply a helmet that was able to circulate water. Older suits covered the whole body and had lots of padding to prevent the suit from being damaged. During his mission to Kinooine, Kiro was able to create a makeshift water tank by combining a flight helmet with a portable water tank, which indicated that these were not the most complicated machines.