I am setting up a 180 gallon tank -60in Length / 24inwidth and 29 in deep - LFS sold me 2 400 W Icecap MH which I am undermounting in the cap - LFS #1 claims that a couple of fans is all theheat control i need - LFS #2 insists i need a chiller - just upgrading from a 55 gallon that i never had this problem with - who is right?