robitreef

I know that many reef hobbyists use 10,000K bulbs -either PC or MH, but what about for planted tanks?

Rolo

They work well on planted tanks too, many use them. Kelvin ultimately is for your color preference.

robitreef

Rolo, I have never seen a 10,000 K PC. I have seen 14,000 and 20,000K MH and they produce a really blue light, but not as blue as actinics. Does the 10,000K produce a nice crisp white light? The 6500K's I have look white when viewing the lights, but the tank looks a little yellowish.

glenhead

I have a pair of the 55W GE 9325K bulbs (which are obviously danged close to 10kK bulbs) in a 4ft strip light. They put out a good white light, and the plants are slurping it up. I changed from 6500K bulbs, and know what you mean about the yellowish cast - though they look nice in my 20gal unplanted tank for the livebearing fishes (Pineapple Swords look good, but the Endler's Livebearers look a bit bland compared to the 9325s). Granted, I also more than doubled the watts per gallon, too, so that has more to do with the plants' happiness than the color, but the plants and fish look great. The Tetras (Black Neons, Lemons, and Glowlights) really pop with the 9325s. The reds of the Alternanthera and Ludwigia are especially nice with the whiter bulbs.

Glen

bharada

This is a textbook case of Kelvin rating having little to do with actual light color. While the typical 10000K bulb will put out a very stark white light, the GE 9325 is very pink/purple. This is very evident with light spillage onto walls.

What I've used over my 40gal breeder are 8800K 96W PC bulbs. Still a white light, but a little less harsh than the 10000K tubes I tried previously. I agree that 6700K tubes tend to have a yellow cast to them.

trenac

A 10000k bulb gives out a blue white or bluish tint. Individuals use any where from a 5500k-10000k bulbs, they mix/match depending on the color effect they are wanting.

robitreef

I'm reviving this post with a couple questions: For anyone out there using the 10,000K PC's:

Have you found this temperature to be detrimental to your plant growth? I believe I read that plants with red pigments will not look good with this type of light.

Has anyone mixed 6500K with 10,000K and what have been the results?

I would like to try the 8800K, but they are square pin configuration and I have straight pin PC bulbs.

david lim

As plant growth is concerned, most bulbs produce enough light in the red and blue spectrums to grow plants, regardless of K rating.

With that said I find that K rating comes to personal preference. Many people like the more yellow warmth look of 6500 K bulbs. Some like that pinkish of the GE aquarays 9325K, etc.

I like the 10000K bulbs, but be careful of the manufacturer. I have found that some 10000k bulbs are fairly yellow (for example from petsupplyliquidators.com). I use a geisemann 10000K MH that many reefers consider to be too yellow, but I find it's perfect. It's the only bulb over the tank.

For PCF I really like the way the 9325K aquaray mixes with a 10000k bulb. I've also tried the 6500K/10000K combo but I find the latter beats it out. These are all just personal preferences though :0).

David

Rolo

I'm using the 8800k in a 4x65w STRAIGHTpin aqualight. It is more then possible...what fixture are you using?

robitreef

Rolo,

I have a fixture from Pet Supply Liquidators- A 48" 4X55W PC fixture. Where did you find the 8800K straight pin bulbs? I believe 65W will work on my fixture (correct me if I am wrong)? I like the look of Amano's tanks, where he has a whiter versus yellower light. I think Jeff Senske mentioned in another post that Amano uses 8000K HQI in his tanks.