Help still confused

[drparker]

I've been researching 150w MH DE bulbs for days and can't decide which to buy.

XM 10k
Radium 20k

I've got a Outer Obit fixture 2 MH bulbs and two 130w PC that are actinic 03 / 7100, dual blue, over a 75g tank with SPS corals.

I'm leaning towards the XM 10k for PAR value but wondering if the 20k Radium would be better for coral coloration.

What would you do?

 

[Toddrtrex]

Not sure how helpful this will be, since different bulbs and what not, but......

Over my 58 I used to run 2*175s, I was running 10XMs, but it was blue enough for me (( using 2*96 PC actinics )). So I tried 20K XM, and while I liked the color, it was just too dim for me. So I upgraded to 2*250, and have been using the 20 XMs, and very happy.

So what I am getting at, is I wonder if the 20K Radiums might be too dim with the 150 version over a 75. Ever think about a 14K bulb?

 

[Jenisiz]

Simply put, the 20K will not provide as much coral growth as the 10k. However...the 20k will make the coral color "pop" more....but then again, that's what you have tenics for.

 

[drparker]

I had looked at the Phoenix 14k but thought they'd be too dim, I couldn't find a PAR for the 150w. The Radium are suppose to have a higher PAR than the other 20k and even 14k. When I looked at PAR ratings on Sanjay's site 150w 10k bulbs range from 57 to 61 most 20k are 20 to 23 but the Radiums have a PAR of 47. That PAR rating on the Radium 150w is equal to the PAR rating of XM and Coralvue 250w 20k.

Thus my confusion, is the Radium 150w really that bright? Will that give me better corals than a 10K?