Power Consumption of MH fixtures.

[bossteck]

I believe so, have just started to use MH ( normal reflector )on a 4 footer. The reflections were all over the ceiling. shadows and temperature were some of the initial observations. I suspended mine 1 feet above the tank, there was a increase of 2-3 degrees. Will observe the electrical bill and share with you guys later.

I believe 1 Watt of MH consumes exactly that, 1 Watt. So it doesn't matter if you're using 200W MH or a 200W of PL the power consumation is the same. (Or am I wrong)

So why people says it takes more electricity to run MH, I suspect it is from the fact that you will be running more fans, air con, or chiller.

[tawauboy]

..................... Still trying to get another timer to do noon burst to further save electricity. [I need stuff that works with 220-240V not 100V! argh!]

.....

you can purchase a step-down transformer for your 110v equipment.

[StanChung]

I have but the problem is I'm neither here nor there. The timers here are a not made for 100V. The lights are 100V. So a bit pissed I have to find 100V rated timers. [the ones that claim to work from 100V to 230V don't work well, works slower by as much as 10%] Weird.

Sorry out topic...

[tawauboy]

don't worry about havin exactly 100v for lights or timers. those designed for 110v operation can tolerate something like 85~125v.

the issue of the timer being inaccurate could be due to the frequency. 110v is 60hz while 230v is 50hz.

[StanChung]

Hi Thomas,
Could be why the thing slows down. Timer's fine if power is off [it has internal batteries] but when power is on it slows down. Thanks for lending your insight.

[blackBRUSHalgae]

I believe the surface area of the tank is important for dispersal of heat. I have come to that conclusion because for my 5x2 tank no prob with heat with just one fan.[2x150mh + 4x36W pl -8 hours daily] 26-28C depending on day. Now that i want the growth to be slow, it's 6 hours daily. Still trying to get another timer to do noon burst to further save electricity. [I need stuff that works with 220-240V not 100V! argh!]

Mine is about 14" above tank. too high [glaring for living room when sitting]

Mine is seating only 8" above the water! My only concern is excessive heat emitting to the surrounding not only from the 2x150W HQI, but also my chiller >.<"

Hi Stan, why is there a difference in your voltage?

Very sorry Altum_lover for hijacking your track ^_^\

[StanChung]

The light fixture is from country that uses 100V.

Sitting just 8" above water for HQI's may give the cone light effect, if you like it then it's ok.

As for power consumption, if memory serves me right watt is the power consumed joules/second-assuming your ballast and light fixture is rated the same.

[David Moses Heng]

Mine is seating only 8" above the water! My only concern is excessive heat emitting to the surrounding not only from the 2x150W HQI, but also my chiller >.<"

Hi Stan, why is there a difference in your voltage?

Very sorry Altum_lover for hijacking your track ^_^\

no issue bro

[tawauboy]

mh is actually better than fl.
mh emits 27% visible light, 17% ir, 19% uv and 37% heat.
fl emits 21% visible light, 37% ir, 0% uv and 42% heat.
your tank water heats up due to the ir.

[StanChung]

Hi Tawauboy,
The data you provided is very interesting as I do get singed a little touching the aluminium luminaires of PL's. Care to name your source of this data?

Air is a poor conductor of heat according to an electrical engineer friend. This is confirmed by the results I have. So MH that has to be hung higher anyway does not really have impact on the tank temp IME.

[StanChung]

Here's an old thread with for a good read and understanding of what is what by Ivo Busko who took the time to compare a lot of lamps.
http://www.aquabotanic.com/lightcompare.htm

[tawauboy]

the source is from united states department of energy.
see this article

still air is a poor conductor of heat but moving air does "move" heat by convection.