Thanks guys!!!

I hadn't heard this but my experience's are that same as LeighMo's
that's why I asked.

When I replaced my 18 watt bulb last week the only temp they had was
10000K. I've used 10000K before and didn't have any problems with
them. At that time I was using them out of choice and found I didn't
like the color. Now - it seems - I have no choice but to use the
10000K until I can find a new source of 6500K 18 watt bulbs.

But I must say that my Blue Betta looks pretty spectacular under all
that blue light!

Thanks again,

Ed