I have a 180 (72x24x24) and I run two radions. According to guidelines I should be running three. I don't see the need. With proper coral placement I won't need to drop the extra $800 on a third unit. I actualy don't mind the minimal shadowing that I see in my tank, in fact I kind of prefer it. Just my 2cents.
I totally love my radions and would recommend them to almost anybody but if I were you though I'd wait until the new GHL and Vega come out. That way you can say that you've explored all of your options. Besides you never know if they come with an extra color like burnt siena or tropical green. That could be very important
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