For three years my 55 gal tank has done well under a pair of Iwasaki 250 watt 6500K MH. It's time for new bulbs and I was considering switching to 10,000K bulbs. My corals are growing just fine now, but you always wonder "Could they be doing better?" I realize any changes I make to the system would require the inhabitants to make some adaptions, but is this change in Kelvins extreme? Thanks.