lighting questions

[Murray]

I'm confused with all the different choices of lights and colours required for a reef tank. I'm new to the hobby and in the learning phase. I hesitate to go with MH lights because of the initial cost as well as the heat output. Can some one tell me the significance of the 10000k bulbs as compared with 65000k or less.
Does anyone have any experience with the new T5 flourescent lights? By the time i'm done with my tank I would like to have some soft corals,annemonies and tridacnid clams. Would several of the T5's give enough light?
Thanks in advance for any suggestions. Murray

[saltaholic]

ahh yes the lighting decisions...many of them!! Here is a great thread on the differences of color of MH and other great info

MH halides compared (http://archive.reefcentral.com/forums/showthread.php?threadid=254667&goto=newpost)

What size tank do you have. Check out reefanatic.com and look up the PFO ballast. For a dual 250watt ballast and 2 ushio 10k 250watt plus sockets and reflectors I paid just over 400 dollars, Which I thought was pretty decent. I am very happy with the setup. With a canopy that I built myself installed w/ fans keeps the heat in check.


Hope this helps.:)

[GDW]

Greetings Murray !

Your tank's height is a critical issue, given that some of the prospective animals you listed require intense light to truly thrive.

The 10000K and 6500K numbers you read about refer to the bulb's spectrum. K stands for "Kelvin", which is a metric heat measurement unit typically used in the aquarium industry to describe the "color" of the light that a bulb emits. 5000K refers to "natural sunlight." Values less than 5000K refer to colors shifted towards the red (infrared) end of the spectrum, while values greater than 5000K refer to colors shifted towards the blue (ultraviolet) end of the spectrum.

Higher K values are desired by reef keepers for two primary reasons: (1) As natural sunlight attenuates (scatters) through a vertical column of saltwater, its spectrum shifts towards the ultraviolet end of the spectrum. It is this "blue" light that the photosynthetic algae make use of (although not exclusively) to produce food to feed the coral, or mollusk, which houses them. This is why all lighting appropriate to reefkeeping have K values above 6500K; (2) The pigments within the photosynthetic algae fluoresce as the light which strikes them is shifted towards the blue end of the spectrum, i.e., more "blue" means more spectacular color in the tissues of your corals.

For what its worth: It's not about the light hitting the surface of your tank. It's about the light that strikes the animal tissue that contains the photosynthetic algae.

Metal halides emit light that does not scatter as much as other bulbs as the light passes down through the height of your tank. You pay a price for this (literally) in terms of upfront invbestment and heat emission (althoguh the long-term maintenance costs of metal halide systems is less than that of other systems). Depending upon the tank's location, you may very well need a "chiller" to compensate for the halide's heat emission (chillers are generally a good thing anyway, but they are an expensive good thing).

I have just begun to play around with T5 bulbs recently, so the opinion of others will be more useful to you regarding their use. My preliminary/limited opinion: I like them. I like their output. I like their size.

Which brings me to my final comment. Consider that you have fundamentally two options in choosing your lights, dependant upon where your animals will be located in your tank. If you want your clam(s) down in the sand, you'll need halides (in my opinion... and everything I've said is just that - an opinion. Get used to this. You're among reefkeepers now ...) to deliver the light down through the vertical water column of your tank. The other option is to pursue a strategy which raises your inverts up to the light source, so that you do not need to worry (too much) about scattering.

Attached is a pic of one of my clams in an 80 gallon reef which uses 4 X 96watt power compacts. I can get away with this because the light passes through only 3-4 inches of water before striking the mantle of the clam.

Sorry for the extended rant .... hope this is useful to you.

[Murray]

Hey thanks for the replys. Gdw, your description of the different colours was excellant and to the point. Since I've gotten this idea to start a reef tank, yours is the only description on different coulred lighting that I've read.
As far as cost for lighting fixtures is concerned the price range that I"ve seen goes from a min. of $1500 up $2300 dollars and that is just way too much to even consider. (That's a fixture with 2 or 3 175 watt Metal Halide with 2 flourescent tubes)
As far as tank size goes it's a standard off the shelf 90 gallon tank,I 'm not too sure of the depth.
Anyway, my thanks to both of you for your replys, all of this discussion certainly helps with the decisions I have to make.

[griss]

Murray,

[welcome]

George

[RichardScottRice]

Originally posted by Murray
As far as cost for lighting fixtures is concerned the price range that I"ve seen goes from a min. of $1500 up $2300 dollars and that is just way too much to even consider.. .

OMG... You need to find another source for your lighting or a less "fancy" lighting fixture. I got 2 MH and 4 PC complete with bulbs for less than $750!

[ddawson]

I'm happy with the T5's on my 40G. Its only 16" tall tank so the light hits the bottom well.

On my old 90G I used MH with two Actinic’s and was very pleased with the color on that setup too.

In both cases I used shallow tanks to assist in getting light penetration.

Dan

[saltaholic]

Like I said I got two 250watt MH ready to light for just over 400. You got to watch this hobby. There are many of places ready to rip you off. Nice thing about RC is so far I have used there sponsers and hava had good service

[Trickman2]

Hey do yourself a favor go here for some lighting
http://www.il-solutions.com/
Or
www.Hellolights.com