Curiosity about blue moonlight LED usage

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Aquarium Advice Activist
Sep 11, 2011
Just got some blue LEDs and they are nice.

My question to you all is in regards to their usage.
Which statement, if any, most closely reassembles your philosophy and/or usage of blue LED moon-lighting for tanks?

1) I leave them on all the time, day and night. The fish don't seem to mind.
2) I leave them on some of the time, but allow some total darkness. I think the fish prefer this.
3) What are LEDs?

What are LEDs??

...on a serious note, I build my Moonlight to watch at my fishes at night, after the time to turn the daylight off if I'm watching the telly or reading a book till late. After that I turn them off as well, so there's no light overnight in my tank. That leaves none of the options above :)
But to be honest I'm curious as well, so I'll keep an eye on the thread!
I have the blue LEDs and 3 pairs of lights on my tank. I have them on timers so I simulate a day cycle twice a day.

What I mean is:
1. Blue LEDs on for 45 minutes
2. Blue lights off, 1 pair lights on for 90 minutes.
3. 30 minutes into the light cycle, 2nd pair of lights on for 90 minutes.
4, 60 minutes into light cycle, 3rd pair of lights on for 90 minutes.
5. After all lights time out, Blue lights on or 45 minutes.
6. All lights off for 90 minutes.
7. Light cycle then starts again with the only difference being the lights are timed on for 2 hours instead of 90 minutes. When the cycle is complete, they stay off for the rest of the night.

Edit: I have the blue lights off when the regular lights are on due to concerns over heat buildup (2 pairs of lights are in the same fixture) and heat sometimes has bad effects on solid-state devices.

To me, this gives the fish a more natural light cycle, plus, by breaking up the light cycle, I dont have as much trouble with algae growth. Also, by timing them like this, I get even usage from the bulbs.
The moonlights in my tanks are fairly dim so I use them as sort of a nightlight for the rest of the room; they stay on 24 hours since they disappear during the full light cycle.
I also run my blue LEDs all the time, with and without the T5HO lamps.
My LFS says there is no harm in it, as far as the fishes' sleep cycle is concerned.
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