Redo my diy aquarium lighting

  • #1
NOOB here.

I am trying to redo my diy aquarium lighting.

Currently I use 4x100 white led xmas lights. And they light great. Problem is, they are multi "8" function lights, I have them on timers, and when they come on, they default to one of the flashing functions, and I have to go at change them to "always on". Each string of 100 has its own box, so i have 4 of these little control boxes. They are smaller then a pack of cigs. 3 bulbs in each string of 25 has a rsitor one the neg side. And they are the 3 bulbs closest to the box, or closest to the neg side. 12 bulb in all has resistors.

So i want to rework the whole setup. I am a mechanic and pretty good with diy, just no led experience. What i WANT to do is cut out the multi function part of the lights, and cut back to just one box or power supply if i can.

So each box has 110 input, 2 wires, and 5 wire output, 1 +, and 4 -, each - wire controls 25 bulbs, and the one + wire runs to the end of each of the strings of 25. I am measuring 109 volts dc as output, but i have a pretty cheap meter.

Can i scrap the boxes and power them with one transformer, or use maybe one of the boxes i have to power all? And how can I bypass the multi function part of the little boxes if i did use them?

All ideas are welcome,



  • #2
curious if i take 400-600 of these lights and make one big panel,,,

What would be a good power sourse to use?

How should i wire the lights?

like they are now, but do 24 strings of 25 lights, or something differant.

I want to keep it as simplle as i can and use the xmas lights i have to do it. I also have several others wanting me to make them lights as well.
  • #3
If you want to build your own LED setup, I would get a 24 volt transformer and a bridge rectifier and a large, electrolytic, 1000 uF 50 volt capacitor.

[PLAIN] [Broken]

This would give you about 32 volts DC out which is about as high as you should be using for safety. Especially near water.
DO NOT USE THE MAINS. Even 110 volts can be deadly.

Then put 7 LEDs in series with a 0.5 watt 390 ohm resistor. This gives a current of about 20 mA.
Repeat as often as you like with more parallel strings, but each string will draw an extra 20 mA.
If you have lots of lights, you will need quite a big transformer.

Do you have a dark area where your fish can go to get away from the bright lights?
Surely they will get stressed if they have those lights on all the time and can't get away from them?
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  • #4
Thank you for the help. I am new to the lingo, but pretty handy with most diy. Love the visuals schematics help me.

I use these lights right now, as is, they are just led xmas lights, and i have a ton.

Want to use as much as i can from them. I have 400 white for day time now, and 100 blue. They get 8 hrs of white, and about 2 extra hours of blue 1 at dawn 1 at dusk. They work great.

Like i said irealy want to eliminate the flashing feature, as it is the default. When timer turns lights on they are flashing, if i am not home to turn them to "on' mode, it could stress them out.

I do not know what resistors I have, each 100 string has 12 resistors now, 3 for each string of 25 bulbs.

I can make panels with plexi, for easier mounting, and to cut back on amount of wires. I just do not know how many lights per string, letc, but you gave some good info to start thinking about.
  • #5
how much transformer would i need for the 400 white, and again for the 100 blue??

I have them on separate circuits and timers, and want to keep them like that i think.

And where do you get these pieces cheap and easy?

thanks again for the straight up answer.
  • #6
fyi in my diagragm i show 7 bulbs in series, but actually the current setup is 25, 3 have resistors, 22 do not. I did not show all the bulbs to save space.

the schematic i posted is my rendition of the actual boxes i have now, again one of these for each 100 bulb string of xmas lights. This is the factory setup, not something i made.
  • #7
Your fish don't understand that there are no predators if they are in a fish tank. So, they are stressed by being lit up so brightly with nowhere to escape.

Try giving them a small covered area where it is dark. If they all migrate to that area, then the bright lights are freaking them out.

It is hard to guess what that control box is doing and even harder to suggest ways of modifying it. However you drew what looks like a large capacitor and this is possibly a timing capacitor for the flash rate.
If you cut one wire of this, (AT YOUR OWN RISK) the flashing may stop. You can solder it back afterwards.
If the flashing stops, it might stop with the lights on or off. This is speculative, though, and again at your own risk if you try it.

It is a lot better and safer to use a transformer and low voltage if you are going to wire up your own LEDs.

399 white LEDs in strings of 7 means 57 strings. If they all take 20 mA this is 1.14 amps.

This is not high power and the components should not be too expensive. A small price to pay for safety.

Blue LEDs use much the same voltage as white ones, but you would have to calculate again if you want to use red or some other colour LEDs.

You will need to hunt around for the components. The transformer would need to be 24 volts at 2 amps or 24 volts at 50 watts. Something like that.
The bridge rectifier should be rated at 5 amps or more. You can get cheap 30 amp bridges that are very rugged and these would be a good choice.
An electrolytic capacitor of 1000 uF and 50 volt rating would be a fairly good choice. Ask for "low ESR". There are quite big charging currents in the capacitor.

Try to get these at a store where you live rather than on-line. You can get advice on which way to connect these things if you buy from them.

You would also need a closed box to mount the circuit in. Even with the box open, it should not be possible to touch the 110 volt wiring.
  • #8
thank you. The fish have places they could go. Whne the lights are just "ON" they are ok. The lights have 8 functions, 1 combination, 2 in waves, 3 sequential, 4 slo glo, 5 chasing/flash, 6slow fade, 7 twinkle/flash, 8 steady on. The default is 1 combination, and some of the flash modes are fast and furious, worse then any lightning strom they might find in nature.

I think the "modes" come from the piece in the iddle. It looks like a little micro processor. AND it has the four outputs that goto what i think are transistors, one for each leg of 25 lights. Also, each leg of 25 lights does the same thing. So the various effects come from controlling each of the 4 legs seperatly, if that makes any sense. I do not know how to describe it. The "transistors" have 3 legs, and one of those legs goes to the micro processor. So it looks to me like that is the controlly feature.

All that is here nor there. If i can run 400 lights at the same brightness that they are now, i will be happy. They are not overly bright, but very natural. There is a big difference between 300 and 400. I had 300 first and added 100 because it was on the dim side. Fish probably were fine, but viewing suffered.

I am fine running a transformer,,, or 2 transformers one for white one for blue. And I might be able to use a few less lights , as new panel design will spread them out more evenly.

just need to know what specs to look for.

thanks again for all the help.
  • #9
thank you, i see that you did provide the specs.

Woudl this be radio shack obtainable? or do i need to find an electronics store of some kind?
  • #10
I see Radio Shack have these transformers:
Model: 273-1512 | Catalog #: 273-1512
Which sound like they would be suitable. $10.49 is a fair price.

They also have these capacitors:
Model: 272-1047 | Catalog #: 272-1047 for $2.59
They are not "LOW ESR" but may be OK to try. If they get hot, you might have to get the good ones.

And they have these bridge rectifiers:
Model: 276-1185 | Catalog #: 276-1185 for $3.29

Oddly, they don't seem to have 390 ohm 1/2 watt resistors although they do have 330 ohm ones which would be OK if you couldn't get anything else.

I have a flashlight with 19 LEDs in it and this can light up our whole back yard. I wonder if you have low output LEDs and might do better with higher output ones?
  • #11
Same parts for the 100/98 blue light system?

Thank a lot by the way.

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