well then it is all to late as I have a Mr SF but am looking at anothere system the way i have my setup i cant have much else what do you know about the nexus also what i need to keep in mind is, im away for long periods of time (4 to 5 weeks) so have to pay someone to look after my pond when im gone, as my wife is to busy with kids and there is no way she is sticking her hand intoo that sand filter. but must say my water is clear and everything seems ok at the moment well was 4 days ago when i left.