I already own 2 x Mitras HV on my 450L tank that Measure 58"L 23" W, 28" high and currently I have them in this formation [] [] and I can see the spread easily covers both front to back and side to side.

Due to the great growth ect ect I have decided to get a new tank built 118" L (3M) 20" W( 50Cm) 20"H ( 50cm) but here is the issue I was wondering if I change the formation and run them = = = then could I get away with 3 Mitras that would be positioned from Left to right roughly - L 650cm - Middle 1500cm - R 650cm from edge.

I am happy if the edges of the tank are not fully lit as I am running my low Sps islands starting in around 350cm/450cm mark from each edge, due to cost I want to see if I can get away with 3 without is looking £$%^ or cheap

I plan on running the GHL around 10-15cm above water so this will also have an impact on spread (any more then that they burn my eyes when on the sofa

I also need to start thinking about bracing so this will be important for me where the GHL's will go

Advice or opinions would be much appreciated