O, I forgot to mention, I like them, all have been good, Except the 1700 will not start when plugged in, needs to be influenced, the 400 has no head presure, I have to run the UV sideways, the 2500's are working well, but the 4' head is not as advertised, ( due to the 90 deg pvc in my return) so I run 2 pumps now.