Small Disclaimer: I was literally about to start a thread/rant on how poorly my corals responded to bulb switching, specifically Aquablue Special, and Giesmann Tropic 6500k -- They're great lights, but they were too much for my system. Those bulbs with 6500k spectrum are
strong. And not all corals (even SPS) are ready to handle them.
I have a 6x24 ATI and an XHO: tank is 24x24x18 (45g Cube, 2" shorter than a 50g) and I will tell you right now -- You will NOT notice the XHO when you have T5's on. I can't notice it at all when I have all 6 bulbs on, but it's there with only 2 bulbs on.
My bulb combo: before I messed everything up was 3 Blue+, 2 Coral+, 1 Actinic (the actinic could have been switched out for a single purple, or another Blue+ pretty easily). Here's a pic with the 3B+, 2C+, 1Act -- This was taken a few days before I ruined it all (lol)
These next two pictures were a few days prior
So that's what my setup looked like with those bulbs BEFORE the XHO. Shortly after this a bunch of bad happened...
- Alk spike
- no3 spike
- Giesmann 6500k burned some SPS
- New bulbs + new lighting schedule made it worse
- Added XHO -- Couldn't visually see much difference...
- XHO Burned corals again -_-
So right now everything looks like 50 shades of beige. IMHO, if you *really* want more pop -- The XHO probably isn't what will make you happy. Especially because at 60 watts for a 24" bar it puts out a TON more light than it looks like. You can easily cook a frag with 'em.