clear vision, would you not be better just buying a secondary shurflo, you can run it without a varistream if you don't plan to use it all the time.
on our smaller trailer system we use one pump (5ltr/min shurflo) with a varistream. If I need to connect a second reel into it I just use a y splitter. It can easily cope with 2 men working with 100m of minibore even on initial cleans.
Lastly, what makes flojet so special - I've repaired 4 of them in the past, all less than a year old (pump motors burnt out), have only ever had 2 Aquatec pumps fail and 1 shurflo. Bear in mind how expensive the flojet are as well I can't see how they are any better (or even as good) as shurflo.