10000k vs. 20000k

ok i want to replace my bulbs 1 fixture is 2 compact floresence bulbs each of 65 watts. the other is 2 no florecance 40 watt bulbs. the 2 40 watt bulbs i want to put as 2 true actinics. the 2 compact bulbs i dont know if i should go with 6, 8, 10, or 20000k? do i want to go for brightness with the lower k or does that not matter? i was told the lower k is more bright. but the color would be more twords the yellow end. what would be better. i have no money for mh. anyone want to give away a mh hehehe.

 

I'd go with a 10K myself. On second thought, you might over power the actinic with the amount of 10K being blasted, so a 20K might suit you better. It really is a matter of opinoion though, both will grow corals just fine.

 

what do you mean by overpower?

 

If you can get true actinic then you could get the 6k PC's & still have a nice color, I'm Almost sure you would get a better PAR performance penetrating the water with the lower kelvin lamps.

 

I've always thought the higher the Kelvin the deeper the penetration because of the higher wave length. If you want to penetrate deeper with lower wattage bulbs you want higher kelvin IMHO.

 

I aint real big on PC's myself but I assume they are like the rest of the lamps and 20000K equals lower PAR output. 10K lamps shouldn't overpower the 40 watt actinics at all. I ran a setup like than for a while and it looked very nice. There are now some 7K10K combo lamps that might do well too. Not as yellow as the 6K but more PAR than a 10K.

 

what is PAR?

 

Pardon what I am sure will be my spelling but "Photosynthetically Active Radiation". It is the spectrum of light the critters utilize. Lower K color lamps (around 6700K) tend to provide more energy within that spectrum than the higher K colors like 20000K blue.

 

Blue does penetrate better to some extent, but our tanks aren't deep enough to make mich differance ... it takes 15-30ft of water to filter out all the red. 20k bulbs are so much dimmer than lower k bulbs that any differance in penetration is negligable.

 

so if i go with 2 40 watt no bulb and 2 65 watt 10000k pc that should be perfect? for a 75 gal tank?