Where to put my heaters

[Kirky88]

With the set up I have purchased it included 2 heaters where should I put them.
Either both in the display tank
Both in the sump
Or 1 in each

 

[obscurereef]

Both in the sump if they fit. Might just need one.

 

[LaWoWee]

+1 for sump. out of sight and directly in waterflow.