This is what I said in the PM
Yea, I am sure that that PP would be more then enough. Right now both of my tanks that have Haddoni's have an 8 hour photo period. I am sure that I could go less, but I have them set up to be on when I am home.
And with those lights you will be more then fine. For about 3 years I had my tan one under PC's -- had to feed more back then, but it was still doing good with them. But, does look better under MH.
And to add to it, my 58 has 2*250 20,000Ks SE, and my 75 has 2*250 14,000Ks DE.
Part of the thing that I noticed with Peter's post is that talked about incredible growth -- I am fairly happy with the size of mine, so I don't feed as often as I used too. So if I wanted mine to get larger I would extend the photo period. And none of my 3 are reaching for light, and pretty much stay in the same place -- unless I screw something up.