The 2250 replaces the Shark-120 and Shark-240. The 2250 TX replaces the Shark TX.
AquaMetrix has been making analyzers for over three decades. In 1990 the 2200 series debuted and have been so highly regarded for their durability that most are still in use and customers still insist on sending orders for them. The Shark controller and Shark TX transmitter were introduced in 2006 as multi-parameter analyzers that switch between pH, ORP, conductivity and flow.