A thread I came across

[untamed]

Originally Posted by banditpowdercoat

WHats the point of a surge tank????

Water is slowly pumped up to a holding tank which is above the main display. When the holding tank hits a certain volume, it rapidly dumps it's contents into the display. This creates a large wave (or surge) and simulates ocean conditions. It is another way to create random flow, as well as a nice way to suspend stuff that may have settled somewhere.