Elementary 10000k question

[105man]

What is the difference between a plain, simple 20w white flourescent and a 10000k flourescent?

I have a 54 gallon reef tank with only hardy, soft corals (mushrooms, polyps, leathers), and I am wondering whether I should replace the basic white flourescent with a 10000k. I realize there are many upgrades beyond that and tons of advice about lighting, but I haven't seen anything just addressing what a 10000k flourescent (not a compact, no special ballast, etc.) would do, if anything.

Thanks!

 

[PeeJ]

first and foremost, it will make your tank look a lot better

 

[105man]

That's a good start! Thanks.

There's one at Foster & Smith, by Coralife, 20w, for $23....does that sound like a good one? They also have something called 50/50, and also 20000k...what Id like is something that looks better, does maybe a little bit of good for the corals and other livestock, and doesn't throw off a lot of extra heat or require special ballasts.

What do you think?

 

[105man]

That's a good start! Thanks.

There's one at Foster & Smith, by Coralife, 20w, for $23....does that sound like a good one? They also have something called 50/50, and also 20000k...what Id like is something that looks better, does maybe a little bit of good for the corals and other livestock, and doesn't throw off a lot of extra heat or require special ballasts.

What do you think?

 

[105man]

That's a good start! Thanks.

There's one at Foster & Smith, by Coralife, 20w, for $23....does that sound like a good one? They also have something called 50/50, and also 20000k...what Id like is something that looks better, does maybe a little bit of good for the corals and other livestock, and doesn't throw off a lot of extra heat or require special ballasts.

What do you think?

 

[PeeJ]

IMO, I would order a Corallife fixture. You can get a 96 watt 50/50 quad set up for like 90 dollars online. Your corals will love it, and it will make a huge difference in the tanks apprearance.

 

[Expos Forever]

10000k and 20w are apples and oranges. K refers to kelvin (colour temperature). W refers to wattage (intensity). 50/50, Daylight, Actinic etc... refer to colour temp (5000k is yellowish - 20000k is blue). Normal/acceptable range is 6500k to 20000k.

IMO the BARE minimum lighting you should have for your tank is a dual 40w fluorescent strip (one daylight, one actinic or 50/50 for example). As you know, more would definetly be better: PC,VHO,MH, etc... In other words simply changing the bulbs will not solve your lack of lighting.

 

[Expos Forever]

Man, do I type slow. I agree with PeeJ's recommendation, IMO that would be sufficient to provide for your corals. Of course clams,SPS , etc... should still be avoided. It's cheaper than replacing corals

 

[PeeJ]

For what it is worth, I have a 75 gallon tank with dual Coralife 230 watt fixtures and it is awesome.

 

[Jime]

When the radiating object is heated to a relatively low temperature, it burns red. At a higher temperature, it turns whiter, and then finally blue. If you were to light four equal sized bulbs in sequence starting with a 2700 k bulb, then a 6700 k bulb, then a 10,000k bulb and lastly a 20,000 k bulb, you would see a distinct difference. The 2700 k would look dim white with the presence of a lot of green, yellow and red. It would look like a low quality desk fluorescent. The 6700 k would look like the color of daylight (it is). The 10,000 k would have a bright blue cast. The 20,000 k would have a distinct blue tone.

Here's a link that may help answer your question.
http://www.thereefweb.com/lighting.htm

 

[105man]

I do have a blue actinic in the fixture as well. Just wanted to know whether replacing the white with a 10000k would be worthwhile. If the only choices are leaving as is, replacing white with 10000k, or replacing white with 20000k, what would you do?

Thanks!

 

[Reef Guy11]

If that is all you can afford then go with the 10000k it will be a bit brighter. But if you ever want to have a good growth rate and enjoy your tank more, then you need to save those bucks and invest in good lighting PC, VHO, MH Etc okay so just keep what you have in corals and don't buy more coral that need more lighting, until you can afford better lights.

 

[105man]

Thanks...I will take that advice to heart. I don't intend on any more corals, and certainly no hard corals or anything more sensitive.

Will the 10000k, assuming same wattage, be more or less bright?...I thought I had also heard that more kelvins makes it somewhat less bright, fewer lumens.

 

[Reef Guy11]

They might be a little brighter but just keep everything pretty close to the top okay.

 

[Anonymous]

Neither 40w bulb will be brighter. However, bulbs at 5500K to 6500K will have a better CRI(color rendering index). Natural sun has a rating of 100 CRI. I believe that the philips 5500K bulb has a CRI of 91 making it one of the best scores around(I believe a 7100K actinic bulb has a CRI of 80). They are considered the best for photosynthesis, but not as asthetically pleasing.

It really comes down to what you think looks best. If you like it bluer, go for a higher Kelvin rating like 10000K or 20000K.