led lighting idea

[mr funktastic]

i have been reading up about LED lighting. i am just curious how far out of the box people have been looking to find cost effective solutions to this. i know there is Taotronics, rapid led, the chinese units as well as many others. but i was looking to spend about 50 bucks. wanted to provide about 40 watts of led over a 15 gallon tank. im curious as to how much kelvin comes into play. what colours should u be looking for. what specific numbers should i be looking for in the description of the led. when it comes to tvs u look at contrast ratios and refresh rates and stuff. so i assume leds have certain numbers u want to see. here are a few options i have found

this is a small self contained unit. puts out 20 watts. description states its waterproof and is "cool white"
here is a link to it

Luminous: 1800LM
Beam Angle: 120 degree
Life Span: 30000 hours
Shell Material: High Strength Aluminum
Mask Material: 5mm High Strength Glass
Ingress Protection: IP65
Dimensions: L200 x W170 x D140mm (approx)
Net Weight: 1.2Kg (approx)

there is also another identicle unit but with selectable colours between red/blue/green/purple/white etc

any opinions are welcome. the unit is only $25. the colour changable one is $45.

 

[oyf709]

its really hard to say, unless they would provide you PAR/PUR raeding and also spectrum.

The main reason is that even it is "cool white" it could be a lot different in spectrum. The only concern most people have would be the way how they make these units are not for aquarium usage and therefore their main stats would be how bright "lumens" the light gives out. Without the actrual spectrum graph, you really not sure what kind of light you putting in your tank. And I think for those got full tank of coral in there won't risk to test it out.

That being said, I have saw someone on 3reef used 3 of these similar type of fixture and they said they are fine with it.
PS: I read about what you trying to do but putting 40W of LED on your 15g tank is enough to bleach all your coral. If you want to pay about $50.00 and able to have enough to light up your 15g tank, i would suggest to use some PAR38 bulb. Some of the lower watts one (12 to 15W) should be enough to keep most of the coral alive.

EDIT: General Rule of thumb is : The higher the watts per LED the fixture has, the deeper/further lights can travell /penatrate. So if you have 1 single 50 or 40W LED chip, the usage for that I would assume is more of a spot light in places like stadium where they need those light able to travel far enough to get to the field

 

[mr funktastic]

the bulbs say they are rated at 6500k for colour. i didnt know that led required so much less light. i was running a 65 watt power compact set up over my 15 before and everything was very happy. i knew u didnt need as much light with led but i didnt think 15 watts would cut it. i will see if i can get a par/pur spec sheet on the unit.

 

[oyf709]

it is the amount of PAR/PUR LED is able to provide (different brand/different current can result in different PAR/PUR reading)
The reason why LED are energy efficient is because they use less power (Watts) to provide the same or even more "light".
Therefore the watt per gallon doesn't really work for LED.

Again, when I say 15W PAR38, it really depend on your application. Some people like to have SPS in their nano even pico tank, then no, 15W PAR38 might not be enough, but you be suprise that it can keep LPS and soft coral without any problem

 

[bigben2057]

i have been reading up about LED lighting. i am just curious how far out of the box people have been looking to find cost effective solutions to this. i know there is Taotronics, rapid led, the chinese units as well as many others. but i was looking to spend about 50 bucks. wanted to provide about 40 watts of led over a 15 gallon tank. im curious as to how much kelvin comes into play. what colours should u be looking for. what specific numbers should i be looking for in the description of the led. when it comes to tvs u look at contrast ratios and refresh rates and stuff. so i assume leds have certain numbers u want to see. here are a few options i have found

this is a small self contained unit. puts out 20 watts. description states its waterproof and is "cool white"
here is a link to it

Luminous: 1800LM
Beam Angle: 120 degree
Life Span: 30000 hours
Shell Material: High Strength Aluminum
Mask Material: 5mm High Strength Glass
Ingress Protection: IP65
Dimensions: L200 x W170 x D140mm (approx)
Net Weight: 1.2Kg (approx)

there is also another identicle unit but with selectable colours between red/blue/green/purple/white etc

any opinions are welcome. the unit is only $25. the colour changable one is $45.

They had those on ebay and I started to read the seller feedback and some of the units seem to just stop working only after a few mo. of op. i would go with taotronics.

 

[oyf709]

This tank is 11G under a 10.8W fixture that doesn't even have 3w bulb, all the LED being used on this fixture are less than 1w.