Flashing LEDS on a Reef Tank?

[Sailmike]

What if the LEDS on a reef tank were set to flash at a rate too fast for the human eye to see? Many LED flashlights already do this to save power. I've heard that the battery can last as much as 25% longer by flashing the LEDS beyond 10 hertz so that the eye cannot see the flashing. If you have an array of 50 three watt LEDS, one could flash them so that only one LED is on at any given moment, but would look like all of the LEDS are on at the same time and the entire array would consume only 3 watts rather than 150 watts. While the human eye would not see the flashing, would this adversely effect the corals?

Could all of the pumps also be put on a frequency so that only one device is on at a time and therefore only consumes the power of the highest wattage item of the whole reef setup?

Thanks for satisfying my curiosity,
Mike

 

[Retired_AF]

I'm not sure if you could do the LEDs one at a time but it is definately possible to do, say 5 to 10 or 25 at a time as long as you have a controller to do that. My guess would be that a large number of the LED's would be off at any time since they do react quickly to voltage changes. Some of that could be remedied by using a capacitor to hold the charge and keep feeding the LED's during the time the applied voltage is off. Some engineering would be required but theoretically it is possible. My question would be about the effect on the total PAR and PUR values where your corals would be located. You would need a measuring device to see what would happen.

I wouldnt recommend it with electric motors since they work on the premise of expanding and collapsing magnetic fields. Distrupting the current flow adversely affects the magnetic fields and you would probably end up burning up the motor.

 

[Sailmike]

Sorry for the double post. I thought my first post didn't go through, so I wrote it all again. It didn't post for a full 24 hours!

 

[Sailmike]

The LED's shouldn't be adversely affected by flashing them. I've designed and built a simple circuit to flash 20 LED strings for my high power rocket.

I just read an article on PAR (photosynthetically active radiation) and PUR (photosynthetically usable radiation). This link provided great information on the subject:
Aquarium Lighting; Reef, Planted Light Information. PAR, Bulb, Watt, Kelvin, Nanometers, MH, LED.

Providing the right PUR is probably just a matter of selecting the right wavelength or color LED's usable to the corals and won't be affected by flashing them. PAR has a time factor to it (uMol*m2*sec) and will definitely be affected by flashing. This could be solved by, for example, running enough 5 watt LED's at 3 volts and 1.5 amps each, which is 4.5 watts, at perhaps 100k hertz. This would still use only 4.5 watts for the entire array. Some experimenting would have to be done to see if this would provide enough PAR. What do you think?

Thanks,
Mike