dual UVC and chiller interconnect ..

[dadarara]

need advice about which is the more efficient connection method
bellow is what I have in mind. several options.
I have two UVC units 36W each. I know about people connecting UVC in closed loop with fast water flow. I dont have a closed loop in the DT
I am not even sure I should connect 2 UVC. probably will not benefit much from having 2.
also I prefer to connect directly to display tank and not closed loop inside the SUMP. In particular , the chiller I think is better to directly flow to DT and not like many people flow the cool water back to the sump. am I right ?
the 2 redundant pumps I have are DC 10000L/h both. so its plenty for what I need. I can play with the flow as much as I want. so it should not be really a factor.
via the UVC I can push slower while the second line will be fast.
so have the bellow options: whats the better one? or maybe something else ?

 

[air_run]

Technically, all the scenarios would work. Although, just one of those sterilizers would be plenty I believe for your system. I am not aware of the UV manufacturer you have but for reference, an Aqua UV 40w is rated for up to 375 gallons.

The top right photo (schematic) is how mine is setup but, also goes to a manifold as well. I do not have a 2nd return pump though. It works well once you figure out the bypass valves to get all the flow right. I run my setup with only a 1200gph pump so your pump(s) should be fine as my system is about half the size of yours.

 

[dadarara]

thank you air_run. appreciate the input