High-Power LED Fixture for a Planted Tank

[BigJim]

mike8333, I played around with a few formulas including the lumen comparison you mentioned. I got similar ridiculous numbers when trying to match the output of T5HO bulbs. I finally decided I couldn't calculate what I needed very well, so I decided to try ten based on other fixtures I saw and ten is where I got a price break on the LEDs. Pretty arbitrary, but it worked for me. For clarification, I've been running the LEDs at full power since I added the CO2 system. For your tank, I think I'd start as simply as multiplying my setup (24" tank) by 2.5 for a total of 25 LEDs over your 5ft tank. You may be able to get away with fewer.

Bud, thanks. I've still been really busy, so no new pictures. I need to tweak the nutrients anyways, so the plants aren't at their peak. I'm hoping to do another fancier LED build in the next few months.

 

[mike8333]

mike8333, I played around with a few formulas including the lumen comparison you mentioned. I got similar ridiculous numbers when trying to match the output of T5HO bulbs. I finally decided I couldn't calculate what I needed very well, so I decided to try ten based on other fixtures I saw and ten is where I got a price break on the LEDs. Pretty arbitrary, but it worked for me. For clarification, I've been running the LEDs at full power since I added the CO2 system. For your tank, I think I'd start as simply as multiplying my setup (24" tank) by 2.5 for a total of 25 LEDs over your 5ft tank. You may be able to get away with fewer.

Bud, thanks. I've still been really busy, so no new pictures. I need to tweak the nutrients anyways, so the plants aren't at their peak. I'm hoping to do another fancier LED build in the next few months.

Thanks for the advice.
Will work towards your direction!
Cheers!

 

[mp3coupe]

BigJim, how are the led's and led constant driver working for you? I'm about to place an order for the same equipment that you used but have a question. Maybe you or someone can chime in.

You used this driver.
2000mA 30W Power Constant Current Source LED Driver (85~265V)
- 30 watt high power LED driver
- Input voltage: AC 85~265V
- Output voltage: DC 16~18V
- Output current: 2000mA (manufacturer rated)
2000mA 30W Power Constant Current Source LED Driver (85~265V) - Free Shipping - DealExtreme

I was wondering if I might be better off with this driver for 2 dollars more? Is it better to run 2 strings in series and then parallel with the driver above, or just run one string all in series with this driver?
1000mA 30W Power Constant Current Source LED Driver (85~265V)
- 30 watt high power LED driver
- Input voltage: AC 85~265V
- Output voltage: DC 30~36V
- Output current: 1000mA
- Features Heatsink aluminum + FR4 Glass fiber plate
1000mA 30W Power Constant Current Source LED Driver (85~265V) - Free Shipping - DealExtreme

Thanks for any assistance.

 

[BigJim]

The LEDs are working well for me. The tank is a mess right now. The CO2 plugged up for a few days and caused a massive greenwater bloom. I had to shut off the lights for a week to clear it up.

Once again, I'm not an electronic expert, but I think either driver would work. The only advantage I can think of off the top of my head is if you use the driver I used and run the LEDs in two parallel legs, and you develop a short across an LED, you'll only fry one leg rather than all the LEDs.