[dastowers]

:thumbsup: Wow...I love this hobby. After reading for days about lights I am just going to post a question to the field:

I need lighting for a 150 gallon - 6 foot long tank. Heavily planted
* Open top Tank
* Can be LED, MH (did T5 already on two others with great success)
* Would like Pendants or Pendant like lights to hang from ceiling

This is for my personal office where I spend 10 hours most days
It will be an Angelfish species tank -something I have always wanted to do since I saw my first cover of TFH.

Money - well as with most things I don't want to over pay but willing to put out the cash. LOL! This tank will be only 5 feet from my desk so the lights should be quiet.

Thank you for read and I hoping for some guidance.

 

[Hoppy]

YOu could use two 36 inch long Finnex RayII LED lights, in one row across the top of the tank, right on top of the tank, and get about 30-35 micromols of PAR - very good low light.

If you hang the light a foot above the top of the tank you will just about have to use either a custom made LED light or a 4 bulb T5HO light, possibly made for you by Catalina Aquarium. That light would be about 40 inches from the substrate.

 

[dastowers]

Hoppy thanks so much! I honestly was very pleased you answered my question.

I would like to have the lights a foot above the tank for ease of access. The LED have always interested me but were too expensive until I found a link to :

http://buildmyled.com/freshwater-lights
Freshwater Planted Tank Lights - What width of light do I choose for an 18 inch wide tank with the lights hung a foot above? Was looking at two 36 inch one with the suspension kits.

Or: http://www.catalinaaquarium.com/store/product_info.php?cPath=71_83&products_id=1219

These are 250 WATT METAL HALIDE PENDANT LIGHT FIXTURE [PEND250W]

Would two or three work best if I chose those? I really like the look of pendants but would the energy saving of the LEDs be better in the long run?

 

[Steve001]

Hoppy thanks so much! I honestly was very pleased you answered my question.

I would like to have the lights a foot above the tank for ease of access. The LED have always interested me but were too expensive until I found a link to :

http://buildmyled.com/freshwater-lights
Freshwater Planted Tank Lights - What width of light do I choose for an 18 inch wide tank with the lights hung a foot above? Was looking at two 36 inch one with the suspension kits.

Or: http://www.catalinaaquarium.com/store/product_info.php?cPath=71_83&products_id=1219

These are 250 WATT METAL HALIDE PENDANT LIGHT FIXTURE [PEND250W]

Would two or three work best if I chose those? I really like the look of pendants but would the energy saving of the LEDs be better in the long run?

With this combo of led's you'll get a high color rendering index ( CRI ) of 91 at 5500K color temperature. The standard against which all lighting is measure is sunlight with a CRI of 100.

525nm Green
525nm Green
730nm Far-IR
5000K
6500K
5000K
5000K
6500K
590nm Amber
5700K
660nm Deep Red
6500K
470nm Blue
6500K
625nm Red

If you can wait the owners are going to include cyan led's soon. This will fill in the led *blue gap all white light leds have at this time and at the same time improving the CRI.

MH lights are very hot and will cost you money in electricity usage.

*6500K led

P.S. Adding green led's does increase the apparent brightness because human vision is most sensitive to those wavelengths.

 

[dastowers]

Steve, thank you for the information. I would wait but I only have the stock terrible LFS strip that came with the setup. The ballast hums and I am going to go crazy- not to mention the light is awful.

What angle should I chose? Keep in mind I would like to hang these 1 foot above the tank for ease of access.

Select Beam Angle
Narrow - 30 Degree
Narrow/Med - 45 Degree
Medium - 60 Degree
Med/Wide - 75 Degree
Wide - 90 Degree

 

[Hoppy]

I would use 60 degree optics, because that prevents any serious spillover light - the individual LED beams would be about a foot in diameter at a foot distance, but would cover the substrate very well, with lots of light reflected off the glass to the substrate. Once you hang a LED light that high above the tank you can get good lighting with either a single row of LEDs or a double row, with the rows just a couple of inches or so apart.

Because the 60 degree optics make the beam be 12 inches in diameter at 12 inches distance, you will want the light to be about a foot shorter than the tank length, to avoid lots of spilled light at each end of the tank. This will reduce the light intensity near the ends, too, so if that isn't acceptable you will need to allow for the spillover someway, perhaps using a deep housing for the light that blocks most of that spillover.

I'm not yet convinced that we need to be concerned about CRI for planted tank lights. If you don't consider that, the light can be a lot simpler, and less prone to having colored shadows in the tank.

 

[Steve001]

I'm not yet convinced that we need to be concerned about CRI for planted tank lights. If you don't consider that, the light can be a lot simpler, and less prone to having colored shadows in the tank.

Configuring these leds into a pendent style might take care of the expected colored shadows if they in fact do occur, but which hasn't been shown to occur conclusively. For example in this vid http://www.youtube.com/watch?v=4cRHcaPcY8w starting at 5:53 the Acan rep is demonstrating their Prism light. You'll notice no colored shadows. Further into the vid the interviewer at 8:00 minutes mentions he see's no individual colors of light.

6500K leds have a good spectral distribution as is, but they have a blue gap. Adding cyan leds would fill in the gap and hopefully creating a high CRI at the same time.

 

[dastowers]

So two 24 inch LED lights would be better than the two 36 inch lights because of the spill over? I was wondering if it would look too cluttered with the two 36 inch light- which would have to touch. That would be enough light if I chose the 60 degree angle and two 24 inch lights? OR one 48 inch one? Thank you! I am going to order them today once I get the confirmation from you. LOL!

 

[Hoppy]

So two 24 inch LED lights would be better than the two 36 inch lights because of the spill over? I was wondering if it would look too cluttered with the two 36 inch light- which would have to touch. That would be enough light if I chose the 60 degree angle and two 24 inch lights? Thank you! I am going to order them today once I get the confirmation from you. LOL!

Before you order the lights, be sure they will give you the PAR you want. The shorter the LED light, the less PAR it gives you (within some limits.) What specific lights are you going to order?

 

[dastowers]

Update: Spoke to one of the owners Nick at Build My Led for about 25 minutes. He suggested two 48 inch LED- at a 75 degree angle. Freshwater show tank with hanger.

What I didn't realize in my "visualization" of the tank is the LED are only 2 INCHES wide! What? Amazing. I am going to stagger them slightly and will post pics when they arrive.


I can't tell you how much I appreciated all your help - Steve and Hoppy. I will post pics once I get them.

FYI...he does have Cyan leds in stock and can add them if anyone wants them to their light order.

 

[minicrazy592]

I have 3 of their fixtures with my own spectrums and love them. I got to see the "show tank" spectrum the other day. It made the colors just pop in the tank and judging by the pearling, the plants were happy too! Keep us posted!

 

[Steve001]

I can't tell you how much I appreciated all your help - Steve and Hoppy. I will post pics once I get them.

FYI...he does have Cyan leds in stock and can add them if anyone wants them to their light order.

Glad to help. If you speak to Nick would you ask him if they are planning to put these cyan leds into their interactive build applet and let me know? I'd like to test the assumption that adding cyan would produce a closer approximation to noon sunlight then without.

 

[Steve001]

I have 3 of their fixtures with my own spectrums and love them. I got to see the "show tank" spectrum the other day. It made the colors just pop in the tank and judging by the pearling, the plants were happy too! Keep us posted!

Hoppy is worried there will be color shadows on the interior. Did you see any such thing or did you see a even blend of light ?

 

[minicrazy592]

Hoppy is worried there will be color shadows on the interior. Did you see any such thing or did you see a even blend of light ?

I have one spot in my 30C where there's a color shadow and it's in a deep crevice between two rocks. You can't see it unless you're looking directly from the top plus there's no plants in there.

With the 75 degree lens, the color blends at a minimum of 2" (give or take) away from the fixture.

 

[Build My LED]

Hi Steve. Just a heads up...I configured a 97 CRI spectrum tonight that used 2 Cyan LEDs. See if you can better it once the Configurator is live on the website

Nick

 

[Steve001]

Hi Steve. Just a heads up...I configured a 97 CRI spectrum tonight that used 2 Cyan LEDs. See if you can better it once the Configurator is live on the website

Nick

I'll take a look once you have it set up.
Do you know offhand what the color temperature is with that configuration ?

While replying I was recalling when I was a volunteer at the Baltimore National Aquarium back in the late 90's even then I foresaw the practical application of leds in planted tanks.

 

[Build My LED]

I'll take a look once you have it set up.
Do you know offhand what the color temperature is with that configuration ?

While replying I was recalling when I was a volunteer at the Baltimore National Aquarium back in the late 90's even then I foresaw the practical application of leds in planted tanks.

Of course. I built the spreadsheet with the algorithms, so I get to see all of the metrics It was a 5500K spectrum, but I personally don't pay attention to the kelvin scale. By itself, it doesn't tell you anything about a lighting system, as you can have multiple color lights that are the same CCT (i.e. kelvin temp). Various lights can look completely different, even though they have the exact same kelvin temp. I prefer to look at the X and Y chromaticity coordinates and the spectrum, which can be used to calculate the CRI and color saturation effects.

Nick

 

[Steve001]

Of course. I built the spreadsheet with the algorithms, so I get to see all of the metrics It was a 5500K spectrum, but I personally don't pay attention to the kelvin scale. By itself, it doesn't tell you anything about a lighting system, as you can have multiple color lights that are the same CCT (i.e. kelvin temp). Various lights can look completely different, even though they have the exact same kelvin temp. I prefer to look at the X and Y chromaticity coordinates and the spectrum, which can be used to calculate the CRI and color saturation effects.

Nick

Thanks for informing me.

You are right about K temperature *alone not being an appropriate standard by which to determine spectral distribution but my hunch, ( I could be wrong ), is when K temp is coupled with high CRI like you have it will center around 5500K which appears to be the case.

Hears another hunch. A true yellow diode or one very close to true yellow will create and even higher CRI, perhaps even match sunlight at noon.

* In another thread not to long ago I had mentioned how different lights with the same K temperature can and do have different spectral outputs among them.

 

[minicrazy592]

Hoppy I snagged these pics in case you were curious about my color shadows:

 

[Steve001]

Hi Steve. Just a heads up...I configured a 97 CRI spectrum tonight that used 2 Cyan LEDs. See if you can better it once the Configurator is live on the website

Nick

A CRI of 98

• 5700K
• 5000K
• 6500K
• 470nm Blue
• 505nm Cyan
• 505nm Cyan
• 4500K
• 3000K
• 525nm Green
• 525nm Green
• 4000K
• 5000K
• 590nm Amber
• 625nm Red
• 590nm Amber

Other than the CIE chart what information do the other graphs give me ?

One other question does the configurer allow the user to select fixture size? I can only configure a 12 inch fixture.