LED lighting

[armyman16]

Hey I am looking into getting new lights for my 75 gallon tank and I ran across this on Craigslist today:

http://dallas.craigslist.org/ftw/for/3036763790.html

Is this a good fixture?
I wanna be able to grow and keep any corals without having to worry about not having enough lighting
My tank has just finished cycling so I have no livestock in right now but I'm wanting to get rid of my power compact fixture which I have now
Any and all advice is appreciated!
Thanks!

 

[Readingexcalibur]

Seems a little on the Small side. I have 25 LEDs and they push a little over 75 watts. This unit has over 650 LEDs at 175 watts. Do I think it's enough? Probably overkill. Does something seem weird at 160 bucks? Yeah hopefully mr. X tunes in.

Edit - my tank is only 30g but I am making a comparison to the quality of LED.

 

[Flreefer]

It looks like it puts out some decent light, but I would be wary of anything homemade. The builder could really know his stuff, or not. I would be worried that there is some underlying problem with it. IMO, it's a gamble.

 

[armyman16]

It looks like it puts out some decent light, but I would be wary of anything homemade. The builder could really know his stuff, or not. I would be worried that there is some underlying problem with it. IMO, it's a gamble.

Yeah I texted him, asked a few questions and it sounds like he really knows his stuff! I think he either does this for a living or does it in his spare time, he said he's making a purple light strip next week that would look good with it..

In the second picture or even in the first, what are those plug things on the left?
Im sure their for the power source but what do I connect those too?

 

[Flreefer]

No idea... That's out of my league!! It does look like it puts out some light, I would just be afraid of something not manufactured, JMO.
Good luck, either way!

 

[Readingexcalibur]

It's easy for someone to sound like they know what they are talking about to someone who doesn't know a whole lot about the product. Don't get swindled. With this many LEDs, they have to be a cheap led IMO.

Those are the leads that plug into the ballast or power supply. The supply will have male connectors on the Opposite end.

 

[armyman16]

It's easy for someone to sound like they know what they are talking about to someone who doesn't know a whole lot about the product. Don't get swindled. With this many LEDs, they have to be a cheap led IMO.

Those are the leads that plug into the ballast or power supply. The supply will have male connectors on the Opposite end.

Ohh I don't have any of those!
How much would those cost me?

 

[Readingexcalibur]

Looks like it comes with the lights. According to the add anyways.

 

[Saratj1]

A couple things I don't like about this fixture.

One is that the LEDs are not very powerful per led. I believe that this makes a difference. Think of it in extremes. Would laying an LCD tv be a good light for an aquarium, I'm sure they have 30w of LEDs in them. Or a single 30w led emitter? I don't like either I'd like 10x3w emitters.

Another thing is the heatsink doesn't look right for 175w of led light. I can't really see the back of the fixture, but it doesn't seem to have cooling fins, and as tightly as those are packed I would really be wondering how hot that thing would get running 12hr plus without much airflow. But since they are so low power, they may be ok, but still.

It would probably work, and I'd say he has close to $100 in materials so the price isn't too bad. But the design isn't my favorite. I would look for something built with 1w emitters on up.

 

[armyman16]

A couple things I don't like about this fixture.

One is that the LEDs are not very powerful per led. I believe that this makes a difference. Think of it in extremes. Would laying an LCD tv be a good light for an aquarium, I'm sure they have 30w of LEDs in them. Or a single 30w led emitter? I don't like either I'd like 10x3w emitters.

Another thing is the heatsink doesn't look right for 175w of led light. I can't really see the back of the fixture, but it doesn't seem to have cooling fins, and as tightly as those are packed I would really be wondering how hot that thing would get running 12hr plus without much airflow. But since they are so low power, they may be ok, but still.

It would probably work, and I'd say he has close to $100 in materials so the price isn't too bad. But the design isn't my favorite. I would look for something built with 1w emitters on up.

What do you mean 1 watt emitters? Isn't that less than 3 watts?
I probably won't be getting this anyways but just for future reference

 

[Saratj1]

The actual little chip that puts out the light is the emitter. The strips of leds are just that strips of leds.

The 1w individual leds are in a different class, Im not sure what its called its something like high power emitters, or high output. They have individual aluminum baseplates and some (like most of the cree's) can be either 1w or 3w depending on how you wire them and/or what driver you power them with. When you buy them, you should get info on how to run them as a 1w led or as a 3w led. For example I have some Royal blue cree's that are 1w or 3w. If you run them at 3.3v and 350mA they are 1w, and if you run them at 3.3v and 750mA they are 3w. Some other 1w leds are just 1w and cannot run at 3w.

I'd just use 1w or 3w depending on your needs. If you need around 75w of led lighting, It would be easier (in my experience) to use 25 x 3w leds as opposed to 75 x 1w leds. But it just depends on your tanks requirements. And that light isnt that bad, its just If it was 50x3w leds it giving you the 150w of power it would be much better. That was just done to be the cheapest way possible to say you have led lighting, kinda like marineland does with their fixtures.

 

[Readingexcalibur]

Yeah, stay away from marineland "reef ready" fixtures. More like ready to kill lps and sps corals "ready". This is the tag on my nano cube 28g. It has 25 3w LEDs and I am growing sps effortlessly. You will be looking at $350-$450 for a basic 3w led setup for your size tank off eBay.

 

[armyman16]

Yeah, stay away from marineland "reef ready" fixtures. More like ready to kill lps and sps corals "ready". This is the tag on my nano cube 28g. It has 25 3w LEDs and I am growing sps effortlessly. You will be looking at $350-$450 for a basic 3w led setup for your size tank off eBay.

How many 3W LEDs would I need for a 75 gallon tank?

 

[Saratj1]

I would probably do 2 fixtures of 25 x 3w each, or two fixtures like the one I built for mine using 9x10w LEDs.
search: DIY budget LED experiment
For my build, I would post a link but I'm using the app and not sure how.

I'm a big fan of the 10w hybrid LEDs search on eBay, they are 2/3 blue and 1/3 white, and have great color, easy to work with, will burn your eyeballs out of your head bright.

 

[Readingexcalibur]

will burn your eyeballs out of your head bright.

Lol, I'm with the 2 25 3w setup. Love DIY setups!!

 

[FishEggs]

I would stay away from any led strips for lighting a sw tank. they may light up the tank but being such low power per led i dont think it would penetrate the water with enough lumens for your corals. would be fine for a fish only but then you wouldnt need that much light anyway.

 

[armyman16]

I would stay away from any led strips for lighting a sw tank. they may light up the tank but being such low power per led i dont think it would penetrate the water with enough lumens for your corals. would be fine for a fish only but then you wouldnt need that much light anyway.

Really? I have heard their very good for saltwater reef tanks

 

[Readingexcalibur]

I heard to stay away as well. There is also the heat issue. They all share the same contact point.

 

[armyman16]

I heard to stay away as well. There is also the heat issue. They all share the same contact point.

I thought they were cooler on the water too?
I heard that was another benefit of them, less heat, less wattage means less electricity costs, don't have to replace bulbs

 

[Readingexcalibur]

I thought they were cooler on the water too?
I heard that was another benefit of them, less heat, less wattage means less electricity costs, don't have to replace bulbs

Well yes and no. LEDs still get warm. But at the diode. There is still wattage draw when you have multiple LEDs on a strip. With LEDs the heat is drawn up or away from the fixture. Where a halide for example transfers hear where it's aimed. I was taking about the contact point where it plugs in. 100 LEDs on a strip will create some amount of heat.