I found the pump has to much pressure. I don't use the hose and brush. I drilled a hole in the base of the flexible nozzle, to reduce the pressure. On the unit we have at my brothers place it was aqueous solution only unit, we but 5 gals of solvent and the pump quit in 24 hours. I used the HF solvent in mine. Only bitch i have is the metric threaded drain plug, I want to put a petcock in to make draining easier. As it now is apita to empty on my second drain and fill in less than a year.
.... Yeah, maybe a little of both lol.