The Aqua TROLL multiparameter line includes the Aqua TROLL 500 and 600 five-port sondes and now the Aqua TROLL 700 and 800 seven-port sondes. Product manager Steve Sewell and In-Situ customer Eli Kersh detail the thought behind the Aqua TROLL design and the advantages of rugged construction, low-maintenance deployment and complete antifouling in the field.