an Entity references as follows:
A rowing tank is an indoor facility which attempts to mimic the conditions rowers face on open water. Rowers sit in fixed rowing positions, with a channel of water to either side of the 'boat'. Older tanks used the power of the athlete to circulate water. This experience is unrealistic, and the rowing stroke is not accurately reproduced. Modern tanks move the water past the rowers, simulating the feel of rowing a boat through open water.