I have an Juwel Vision 180 freshwater aquarium in my living room for quiet a few years now. I really like my shrimps and gournami fresh water fishes.
Off-course I made a few DIY adjustments to it. some thermal isolation, external sump filter, UV-filters and an dimmable T8 TL controller are already installed.
But the last couple of weeks I’m getting repeated failures on powering on the dimmable T8 lights. It’s really weird, all wire connections look OK but when I shake the unit it will go ON and OFF and sometimes it won’t start at all. So I made a drastic decision, I will replace the entire (plastic) hood for a DYI wooden hood with LED-strips mounted on it.
I got inspired by this youtube video from a guy that made an Arduino aquarium controller for his reefaquarium.
That thing has a lot of features including temp,PH,salt sensors and light control off-course! So a few late nights of “googling” learned that fabric made LED arrays are expensive. You can’t get a decent LED array and controller of less than 400 euro (600 dollar)!
So I decide to made one by my own. There are a few basic thing that you have to keep in mind if you want to made a LED array for your aquarium.
- Amount of light intensity (lux,mcd)
- Light color &temperature (Kelvin)
- The angle of light
- Power usage & cooling
Light intensity
My current setup is made by the two factory build TL-5 tubes from 25 watt each. The measurements of light intensity is in LUX.
The amount of lumen output is non-directional so the 2209 lumens are reflected in all angles and just a small part is directly put into the aquarium water.
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4’ linear fluorescent bulbs
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Lumen output
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28 Watt T5
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2900 lumens
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54 Watt T5
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5000 lumens
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25 Watt T8
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2209 lumens
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32 Watt T8
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2850-3100 lumens
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34 Watt T12
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1930-2800 lumens
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40 Watt T12
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1980-3300 lumens
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But for calculation of the amount of led lumen I take 2000 lumens (90%) for each tube, makes 4000 lumens total.
Light Color
The most DIY aquarium projects overlook this point. It’s important to look at the color of (visible and non-visible) light that you emit from your leds! Especially if you have plants in your aquarium! Here is a typical diagram of a grow-lux® fluorescent lamp.
You can see that there a spikes at the blue 450 nm and red 675 nm spectrum range. That’s because the photoperiodism for plant react on those wave-lenghts.
But I am not convinced that a red-blue ratio greater than that of natural sunlight is any better than one less than natural sunlight, in fact it could be worse.
If you read www.cartage.org.lb you will learn that high levels of near red light (660 nm) stimulates stem elongation over biomass accumulation (i.e. growing leaves). This is countered by far-red light (730 nm). Most tubes are deficient in far red (from what we can tell from the spectra). This is OK, as once the lights are turned off the Phytochrome resets and undoes the effect of the 660 nm light. Water absorbs red light pretty well in any event so the red-blue ratio at 0.5 m is perhaps more crucial.
So now back to the leds, it is very dificult to get technical datasheets of the leds that are used in ledstrips. a bit of google-ing gives me some value’s of the RGB leds but I’m not pretty sure if the are common for the most leds. (but there aren’t so very mutch led factories in the world..)
Blue :475nm
Green: 530nm
Red: 630nm
So it is almost “right for the Blue spectrum but a 45 nm “off” for the optimum Red spectrum value.
Angle of light
Leds will have a very small beam of light without a proper uses of a lens. A default “plug-in” led from 5 mm will make a beam at an angle of 30 degrees so that’s pretty useless for an aquarium. However the more “A-grade” led strips will have a build in lens that diffuse the light to 120 degrees (at 1meter distance) so that’s pretty good! My aquarium strips a at 55 cm of the bottom so I will have a spead of 60 degrees of light on the bottom. And my led strips are mounted in a parallel array with very short spacing in between (7cm) so there will be a lot of beam crossing so It should be a nice spead of light in the tank.
Power usage & cooling
My old 2 TL-8 bulbs have a actual power usage of 56 watt (that includes the converter and heat losses) and I would be nice to do some power reducing with the use of leds. But that isn’t my main goal of this build. I bought 3.6 meter of led strips with a rate of 14.4 watt/meter so that will be 52 watt without the AC/DC converter losses. 4 watt power reducing on full-power isn’t much but the leds aren’t on at maximum rate the whole day. So I will measure the KWH/day use with a power meter for the TL bulbs and leds to get a fair comparison on the power usage.
So lets get it on and build this thing!