This is the simple, tried and proven method; place a container on the ground, catch the water, measure the water. We've improved on that concept with a light-weight plastic container...no heavy, rusty tuna or coffee cans here. These are square which makes them easy to pour from and low profile to work well with low angle nozzles. We highly recommend you get a pack of our catch can stakes for securing on slopes, if it's breezy, or when displaced by the stream of a rotor head.
