Sorry if I wasn't clear about this. The weights are for the truck, the trailer, all the equipment and no water in the tanks.
Ken
Okay, thanks for correcting that. The figures are more reasonable now but it's the poly tank forward of the trailer axles that is the deal breaker.
You bought and installed a large (600 gal?) tank so I assume that is the quantity of water you needed for whatever job it is you are doing. The tank alone, mounted in the bed of your Ram 2500 pickup, will use all of the available cargo carrying capacity of your truck if it is filled with water.