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Using 250w 20k for my sps tank~~


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read this thread.

http://www.sgreefclub.com/forum/index.php?showtopic=2622

an abstract from the above thread to address ur qns. ;)

Part IV: Kelvin and CRI

Kelvin temperature of light, for our purposes*, refers to the relative blue vs. red appearance of the light being emitted. The redder a light source appears, the lower the Kelvin temperature. Conversely, the bluer a light source appears to be, the higher the Kelvin temperature. Most quality lights sold specifically for freshwater aquariums have a Kelvin temperature of 5,000 to 6,500K, and produce a relatively “warm” white light that is said to simulate sunlight. Bulbs sold for marine aquaria have Kelvin temperatures ranging roughly from 6,500 to 20,000K. The greater relative intensities of blue wavelengths in the light emission are thought to be more beneficial to photosynthetic marine organisms that often live at depths in which very little red light is able to reach. Actually, the higher Kelvin temps may be more for display than practicality. Although sunlight is progressively filtered with increasing depth in ocean water, 6,500K lights are still a no-nonsense approach to providing a reef system with an appropriate source of light. Even so, 10,000K lamps seem to have a more aesthetic appeal to them. Not too blue, not too yellow.

It should be noted that the actual Kelvin temperature of a new bulb sometimes varies quite markedly from the manufacturer’s stated Kelvin temperature. Unfortunately for the vast majority of consumers, there is no inexpensive means to get the actual Kelvin of a bulb, so in a sense you’re at the mercy of the manufacturer’s “word”. This is one explanation for the difference in apparent color of two “same Kelvin” bulbs produced by different manufacturers. There’s no reason to panic, however. Corals don’t care if a light is exactly 6,500K, 7,100K, 10,000K, etc. All they are interested in is a light source that is of high enough intensity, while simultaneously providing the correct wavelengths at the correct relative levels. So if a “10,000K” bulb has an actual temperature of 9,000 or 11,000K, it won’t matter much to the corals.

I will briefly touch on the extremely controversial topic of “which bulb is best”. There is no correct answer to that subject that suits every aquarium. Organisms originate from various depths of the reef, some are in full sunlight, some are shaded beneath other organisms or in caves, some live in water with high turbidity, etc. If your aquarium houses animals that are all found in the same section of the reef in the same “light” conditions, then you can choose a general Kelvin temperature that will replicate the organism’s “natural habitat”. Cases such as this are extremely rare. Practically every reef tank will have a mix of animals that originate in various conditions. Therefore, a wide approach to lighting the aquarium may prove most beneficial. A mix of 6,500K, actinic, 10,000K, and 20,000K bulbs will probably satisfy the light needs of all photosynthetic organisms, provided the intensity of light is high enough. Actually, a combination of 6,500K and actinic bulbs has been a “reef standard” for quite some time, and with good results. Aside from providing the correct light regime for corals, the observer also needs to be satisfied with the entire reef scene. This is one reason that you see few aquariums illuminated entirely with actinic lights. All in all, most photosynthetic reef organisms will successfully adapt to “foreign” light conditions, given enough time.

*There is a little more to Kelvin temperature than my simple explanation above, but it’s more applicable to Physics than to aquariums. When an object is heated to high enough temperatures, it begins to glow (incandescence). The radiation emitted has different characteristics according to the temperature of the object. At relatively “low” temperatures, the object gives off more of a red glow. The hotter the object becomes, the more blue and less red it becomes. This behavior is tested in Physics with an object known as a “blackbody”, which reflects no light, yet radiates light as it’s heated.

CRI or Color Rendering Index is a relative measurement of the light source as it compares to sunlight over the equator at sea level at noon. The higher a CRI is, the more closely that light source resembles the sun in those conditions. CRI is an important factor when selecting so-called “daylight” lamps (5000-6500K), but is of little importance to bulbs emitting a lower or higher Kelvin temperature. If a daylight bulb has a CRI over 90, it approximates the “color” of the sun fairly well, while a bulb with a CRI around 80 is not as desirable. Only a few lamp manufacturers readily advertise information about the CRI of their products, and as expected, these are some of the better CRI ratings to be found in the hobby. Information on CRI of a lamp should be available from its manufacturer. If they don’t have the lamp specs available for some reason, that’s an indication that you’re not speaking to the original manufacturer of the lamp.

By the way, the “standard” actual daylight Kelvin temperature is roughly 6000K.

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In USA and Europe, the Aquaconnect 14k and the Guisseman magnachrome 14k are the two leading 14k bulbs, all of which are available in different SE and DE fittings and in different wattages.

Locally, you can also try out the Phoenix 14k bulb only available in 250w (check out the review by Hon) which bears a visually identical look to the AC14k. There is little or no information about its properties though and no one knows the long term perfomance as it is too new aka... time will only tell if the Phoenix bulb will go the way of the Radium... excellent colour but it ends its shelf life within 6 months because of the loss of intensity and spectral shifts.

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Arcadia confirmed has 14kk since i am using it for the past few months.. looks good in my opinion but i am no expert...

How long have you been using? Does it shift to blue after some time?

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Been using it for about 3 months or so... no apparent shift to blue and its crisp white in color

Very popular with the Euro reefers apparently

Can let me where to get and the price?

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Hi again... one question more in this post. ;)

you who to have proford more lights, as you think that it is the most

advisable temperature (kelvins) for the SPS as far as color????

Me acros the great majorityn torn at green :nc:

i'm use 150w hqi and 14kº (lifetech) bulbs.

perhaps it is an intensity problem and it must change to 250 or 400???

all thks

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From what i understand from the experts, higher K will give better colors so if u want colors, get a 20kk MH.

For intensity, depends on how deep your tank is.. 150w is sifficient for shallower tanks. also dependent on how high the SPS are mounted in your tank.

Will need these kinda specs before the experts can advise you further ..

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exact, that is the disadvantage sps grow better to low temperatures.

But observing your aquariums, I have the doubt that it is better since

many to use lamps of 10,000 and by my earth it seems something in

disuse.

and yours sps is seen very colorful

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My tank is a 3ftx1.5x1.5 and I use

1) 250w BLV 10kk

2) 4x36w Blue PL

The BLV was bluish white initially. Now it is yellowish. The Blue PL added achieve overall bluish white view.

I will be getting a AC 250w 14kk in due course. Read from RC that after the bulb has built-in, it emit crisp bluish white light.

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My tank is a 3ftx1.5x1.5 and I use

1) 250w BLV 10kk

2) 4x36w Blue PL

The BLV was bluish white initially. Now it is yellowish. The Blue PL added achieve overall bluish white view.

I will be getting a AC 250w 14kk in due course. Read from RC that after the bulb has built-in, it emit crisp bluish white light.

I am also using 250W DE BLV 10K - find it too yellowish. Heard that AC 250 W 14K has some inventory problem even in the US. ;) Let me know if you have any lobang on AC 250W. I am keen on getting it also, not in a hurry though.

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