# Please help a newbie!



## Chkinut (Jan 21, 2015)

Hi guys! I'm new to planted tanks and I have an empty 125 gallon waiting for me to get it set up. I was thinking of ordering 4 LED floodlights (outdoor, waterproof, cool white, 50W each, 6000-6500K). Do u guys think these would work for a low tech tank?


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## TropTrea (Jan 10, 2014)

Chkinut said:


> Hi guys! I'm new to planted tanks and I have an empty 125 gallon waiting for me to get it set up. I was thinking of ordering 4 LED floodlights (outdoor, waterproof, cool white, 50W each, 6000-6500K). Do u guys think these would work for a low tech tank?


A 125 gallon tank is 6' long by 18" deep if it is the type I'm thinking about. With flood lights your creating spots of light rather than lighting the entire area . These spot light also created hard shadows so everything under a plants leaves will be in dark shadow. Some people like this others do not. I personally prefer a much more uniform lighting system.

Then there the range of efficiencies for LED's. There are some fixtures where you need almost 1.5 Watts of Light per gallon of water compared to others where you can get away with a little over 1/2 Watt per gallon. So unless you know the detailed specifications of a LED fixture it almost becomes trial and error.

I have had good luck with DIY fixtures for LED's which are very comparable price wise with most better LED fixtures and at least as efficient. In a DIY fixture you need roughly only 60 to 90 watts of LED lighting but even for extreme light not need more than 150 Watts. With Commercial fixtures you be talking anywhere from 125 to 250 watts.

Color temperature and the light spectrum is also extremely important with LED lights. A 6,500K LED gives you a nice looking tank and enough blue light for the plants but there is almost no Red light available for the plants. Similarly a Neutral White LED (4,500K) will make the tank look even better in my eye, and gives a good amount of red light but is very questionable on the blue end of the spectrum. The ideal LED fixture will use both the Cool and Neutral Whites with some even adding a few additional RED and Blue LED's to boost photosynthesis higher.

Looking at a 125 gallon tank an estimate to build your own 72 to 180 watt system would be roughly 36 LED's running on two separate Rails with the LED cost being between $100 and $150 dependent on where you get them. The mounting Rails combination heat sinks would run roughly $36 to $48 dependent on your source. The drivers which would determine the actual wattage could cost as low as $40 for the lower wattage or as high as $75 for the higher Wattage range. Small miscellaneous parts like wire solder and thermo epoxy would add another $25.00.

Total Cost $200 to $300 for a fixture that would compete with using 4-36" commercial fixtures.


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## Chkinut (Jan 21, 2015)

Thank u SO much!! Great info and help!! I appreciate it!!!


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