LED color coverage

[ReeferBill]

Ok, so I am getting a DYI LED set up for my 24 gallon nano tank...here are the specs...

14 RB 3 watt cree LEDs
5 NW 3 watt LEDs
5 CW 3 watt LEDs

I am thinking of getting a separate driver for 2 UV 3 watt LEDs. Any thoughts on if this is needed for color spectrum? I will already have the NW for a red spectrum coverage, and I know its plenty of light for a small tank. But I have read that the UV gives the full coverage for corals. Should I bother or not. Any advice would help.
Thanks,
Bill

 

[Reef Breeders Verified Sponsor]

I would cut the nuetral white, and replace it with 3 UVs 1 red and 1 green. neutral whites really was out colors

 

[ReeferBill]

Hey, thanks for the imput. In my research, most people showed that the NW gave a spectrum of red and green that the CW did not provide. I will not be using any lenses, so I dont want the reds and greens to give a calidescope effect in the tank. On top of that, the UV and reds need to be driven at a lower aperage than the RB and NW/CW. So if I have those on the string, I will have to dim them down quite a bit so I dont blow the bulbs. That is why I was thinking of doing the separate driver, so I still get the UV color, but can do anything with the other LEDs.

 

[jonbar1]

The neutral white/cool white debate is still on going from what I've found. The deep red and cyan/turquoise are supposed to mix with the royal blue to make a slightly actinic white that balances well. By UV you hopefully mean true violet, and they seem to add more to the actinic spectrum and have good par.

I'd probably go with what you are planning and be ready to remove the whites you don't personally like, but I'd get a red and turquoise to play with as well. I'd probably also ad a single regular blue for a better overall look.

 

[ReeferBill]

Well, I am getting a plug and play kit that will give me the ability to change LEDs if needed, but those colors need to be driven lower, so I would have to dim the whole string to avoid damage. I agree the debate is ongoing, but the spectrums from the NW seem to give some of the red, which will allow the LPS to still show red colorations without bleaching to orange. If needed in the future I can change things out. What did you mean by go with what I was planning and add a singe blue for better overall look? What are you currently running on your tank?
Thanks for the help.
Bill

 

[Reef Breeders Verified Sponsor]

What are you running them at? 650-700 ma is plenty bright, 3 LEDs on one string will go out prematurely, if your driver has a forward voltage greater than 9, which I can almost guaruntee it does.

 

[ReeferBill]

Hi Anemone,
I am not sure which string you are talking about, but here is the 24 bulb kit I am getting,
Solderless Biocube 29 Dimmable Retrofit Kit - Rapid LED

and here is the moon light kit that I will put the UV bulbs on...
4 LED Moonlight Kit - Rapid LED

I understand that 700ma is bright enough, but I want the option to dial up the blues if I need to. Or if my kids get a hold of the dimmable switches and turn them up all the way, I would not want the bulbs to blow. If I have the RB or CW on there it doesnt matter, but if the UV or red get in there it HAS to stay at the amperage.
Does that make sense?

 

[cparka23]

[...] 3 LEDs on one string will go out prematurely, if your driver has a forward voltage greater than 9, which I can almost guaruntee it does.

For most electronics, that makes sense. But this is not the case if you're using typical LED drivers. Glance at the data sheet of one and it'll say that the voltage output varies over a range. Running three LEDs will have a total forward voltage of about 9V or 10V, which is fine as long as the combined voltage is within the driver's output range.

 

[Reef Breeders Verified Sponsor]

For most electronics, that makes sense. But this is not the case if you're using typical LED drivers. Glance at the data sheet of one and it'll say that the voltage output varies over a range. Running three LEDs will have a total forward voltage of about 9V or 10V, which is fine as long as the combined voltage is within the driver's output range.

that's what I meant, 15 v to 24v can hurt the LEDs, while 6-12v will not

 

[cparka23]

If you read the data sheet, the voltage range is usually very wide. For something like a Meanwell LPC-35-700 (700 mA), the voltage range is 9V to 48V. Like I said, if you read the data sheet, you'll see that that's the case.

(Hopefully, without getting too technical) Where you'd normally drive some device with voltage, LED drivers are considered current sources. They will run at a constant current no matter what is connected to it (as long as it doesn't need a huge voltage to do it). So if you connect three LEDs to it, the voltage will never get to 15V. The voltage will automatically be set to whatever the forward voltage of 3 LEDs is. This is due to the control circuitry of the drivers that maintain the current and also to the fact that LEDs are diodes.