LED tank light

[kgthomas]

Hi everyone,

I am looking a bit of advice, I have a discus tank and a marine tank, at the minute I am in the process of building a LED light for my marine tank, at the same time I have picked up a few bits and pieces to eventually build a LED light for the discus tank. For the marine tank I am going for white (mix of cool and neutral), blue (mix of blue and royal blue), red, green and UV LEDs. I am wondering what sort of colour mix would I need for a discus planted tank? I have ordered extra red and green LEDs, I know the green LEDs will do little for the plants but I am hoping that they should show off colours well. The reason I am looking into this now is that I am ordering drivers for the LEDs and they have a set delivery price of £10 so when I order the 7 I need for the marine tank it adds £1.50 to each driver but if I know I need 5 for the discus tank then I can order them also at the same time and work out adding less to each driver and saving me another £10 later in the year.

Thanks in advance for any help people can offer

Keith

[ILLUSN]

For a planted discus tank you can get away with a mix of neutral/warmer whites and cool whites. you dont need many my 4x2x1.5 planted tank at dads place runs 63w of epistar 6500k whites (23 leds in total) and punches out more par then my old 4x54w t5 setup (200 par surface down to 20par 2 feet away at the substrate).

the discus display tank uses a full spectrum setup to REALLY display the fish well. it uses a ratio of 2 red (660mn) 2 blue (450nm) 1 green (530nm) and 2.5 white (6500k t6 XML or epistar 6500k). the colours are amazing.

A word of advice if using colours place the LEDS as close as possible together to avoid the disco effect, also if your using RED leds use greens or turquoise (505-535nm). The green light turns the red light yellow to the human eye. This takes away the harshness of the red and more than quadruples the brightness for double the power consumption (human eyes are tuned for maximum response at 500-550nm). Adding a blue led turns the yellow light to a cool white light ~8000k.

[ILLUSN]

heres the planted tank sorry no full tank shots yet.

this is a watercooled light hooked up to an eheim 2228 canister.

i have full PAR measurments but i need to get some more photos before I can post a DIY. the LEDs used in this build are cheep epistar chips $1.08 each. these put out plenty of light with 60 degree optics for a planted tank. the full array pulls 63w

I intend to revisit this light on the October long week end and add another 40w driver with 4 of these chips to increase the colour in the tank.
http://www.ledgroupbuy.com/ocean-coral-white/

For now this is the best I can do before Dad comes back from overseas on the weekend, a little thank you to him for helping my wife out with the kids while I've been settling into my new job :)

[kgthomas]

Hi Thank you for your input on this it is good to see that others are using the same colour mix as I am planning.

I will be controlling using a jarduino controller so I can dim the colours to get the colour I like best so not too bad that way.

I was wondering if anyone uses UV LEDs in discus tanks? They seem to be the must have thing in marine LED systems so I am including it in that. Its also good to see that expensive LEDs are not required as the marine tank needs Cree LEDs which are roughly $3 each.

MEant to ask was your PAR meter expensive as I would be curious as to what I get out of the lights when I am finished?

Thanks again for your posts and for the pictures of your tanks, your fish look to have good colours under these lights.

Cheers Keith

[ILLUSN]

By uv I assume you mean true violet 405-420mn?
To be honest for fresh water they are useless. Our eyes don't see those wavelengths well so they look dim. The colour they give off gets washed out by the other wavelengths and they don't exite pigments in freshwater like they do in coral.

I have some on my BIG project for my altum tank nut I'm just using them as moon lights.

A par meter will cost you 350 for an apogee that's the one to get if you want good results you can compare with others. I use a seneye it does a good enough job for my needs and I like the spectrum chart it outputs

[kgthomas]

Hi thanks for getting back to me about this, sorry about the delay in replying to your post I was out of the country for awhile with no easy access to the net.

The UV lights are 395-405 so only just falling into the visible spectrum. It is good to see that everyone seems to use blue LEDs only whereas with the marine tank I am advised to use both blue and royal blue LEDs.

My tank is 24" deep at the moment so not too bad so should be able to light it easy enough.

Thanks again for the info and when I do start the build I will post on here a thread on it in case it is of interest to anyone on here.

Cheers Keith

[ILLUSN]

no wories Keith, dads planted tank is 2 foot deep, cheap epistars with 60deg optics is plenty, I'm happy with 20 par on the substrate if you want more maybe concider some of the higher output leds like luxeon i (if using 700ma or less) or cree XML or XTE (if using over 1000ma).
If you want to use blue with a planted tank try and mix it with 505nm cyan/turquoise and 660nm red. you plantrs will love it and it looks a really nice 8000k white that really makes your fish pop! I'll try and post some photos of my blueline geos under this lighting combo.

I know you intend to dim the chanels to get the colour right but my expirience is that if you dim the reds down so they dont "streak" through the water they are at such a low output that you get no benifit from them. please concider combining them with royal blue (450nm) and turquoise/Cyan (505nm) that way you run the lot at full power and not have it look terible.

If you were to use 1x 3 color cluster to 1x 5000K XML or XTE you'd have just about the perfect setup for a freshwater tank. If ever you wanted to go marine with this light you'd just add violet and royal blue in 1:1 with what you have and i doubt you'd find a better looking light source anywhere.