Actually, tankers carry more water than hose. The larger tanks create a smaller hose bed, resulting in less hose. The primary function of tankers are for water supply, although some may be used as a primary attack pumper.
Back to the creation, its not bad. I would say that the mirrors are a little too far extended past the truck. Try to shorten it so it does not extend past the front bumper and you should be good to go.
Is this the finished project? If so, it needs a few things. First, a deck gun or monitor is need on top of the pump. Second, instead of having two portable ponds, only have 1 and add a ground ladder plus some hard suction hose. It also needs a hose bed and some rear indicators (turn signal, brake light, and reverse light).