Just wondering, the parallel plumbing of the Vectons (in out in out, hokey cokey) must reduce the turnover/flow of the pumps??
its only 1 pump that drives all the UVs
with UVs is all about flow rate to slow and it will boil the water to fast and they don't do anything
each UV has a max flow rate of 1400 lph
so if my math was right 4 x 1400 should let you pass 5600 lph throw the UVs
it will slow the flow down a bit so i think maybe a 5000 lph pump would only push 4000 lph meaning it will be slower than recommended so should warm the water a bit so should give the heaters less work to do meaning less elec