Hi all I’ve just added 2 new V4’s to my system, eventually I will replace the V2.1s with 4’s but they still have a few years life in them yet. The PAR is now incredible I’m getting 250 on the sand bed and 500 on the upper corals... and I’m only running the V4’s at 50% on all 4 channels the 2.1s are at 90%. Obviously the coverage I’m getting is incredible... I will start playing with the channels and colour blend in a few weeks once the tank has acclimatised to the new intensity’s, but so far I am delighted..