I was on a site in Darlington two weeks ago and when on site i noticed i was one of the few who used a container to catch my dirty water, most others used a home made device it was a piece of drainpipe with two holes for the grey tube to fit into and a series of small holes for the water to trickle out also tis device was stuffed with mesh to collect any solids, has anyone else used this and are they legal to use as it would save a lot of bother emptying the wastemaster.