Apex Trident Reagent Kit (6 Month Supply) - Neptune SystemsTrident Reagent Kit 6 Month Supply With six month kits, the cost of running the Trident is less than $17 per month thats averages out to about 7 cents a test! Neptune Systems recommends keeping on hand no more Trident reagent than you might expect to consume within the next 12 months. 6 month reagent kit (based on the default testing schedule of 4 Alk 2 Ca 2 Mg per day). The reagent kit has at least 760 alkalinity tests and 360 tests each of Calcium