Ok, let's hear it!

[Magickiwi]

MH/T5 combo all the way baby. I can't feature paying 5x as much for a fixture that is almost as good as MH.

Even if you have to buy a chiller you're still looking at a cheaper option than LED...

[Aquattro]

Originally Posted by Magickiwi

Even if you have to buy a chiller you're still looking at a cheaper option than LED...

I still had to run my chiller even with LED, so no savings there

[Proteus]

I've decided to continue with LEDs in my mp10 controllers as I can't find a small enough halide bulb to fit

[Magickiwi]

Originally Posted by Aquattro

I still had to run my chiller even with LED, so no savings there

That's probably 50% of the selling features for LED is that it runs so much cooler. If you have to buy a chiller anyway then what is the point?

[Proteus]

Originally Posted by Magickiwi

That's probably 50% of the selling features for LED is that it runs so much cooler. If you have to buy a chiller anyway then what is the point?

Humidity....

[mrhasan]

Originally Posted by Magickiwi

That's probably 50% of the selling features for LED is that it runs so much cooler. If you have to buy a chiller anyway then what is the point?

Try touching the heatsink; I dare you

The thing is, both LEDs and MH "runs" hot but MH "dissipates" heat (and light) omnidirectionally (since its a round bulb) and cannot be fitted with heat sink to take away the heat. On the other hand, LEDs dissipates heat bidirectionally but emits light unidirectionally and so can be fitted with heat sink on the opposite side with heat sink to take away the heat. And hence the "runs cooler" market hype If some sort of technology comes which allows MH to be fitted with heat, that market tag line is going to be buried.

[Madreefer]

Originally Posted by mrhasan

Try touching the heatsink; I dare you

The thing is, both LEDs and MH "runs" hot but MH "dissipates" heat (and light) omnidirectionally (since its a round bulb) and cannot be fitted with heat sink to take away the heat. On the other hand, LEDs dissipates heat bidirectionally but emits light unidirectionally and so can be fitted with heat sink on the opposite side with heat sink to take away the heat. And hence the "runs cooler" market hype If some sort of technology comes which allows MH to be fitted with heat, that market tag line is going to be buried.

They are not hot at all. Even after running at 100% for hours. I have fixtures with built in fans and other ones without them.

[mrhasan]

Originally Posted by Madreefer

They are not hot at all. Even after running at 100% for hours. I have fixtures with built in fans and other ones without them.

Heat sinks are meant to be hot. They taken the heat from the LEDs and dissipate them to the air but not at a rate which makes it run cool (heatsinks have a maximum heat capacity and stays below that or else the heat sink is not the right one for the system). Don't know why yours run cool Probably you are using oversized heat sink?

[sphelps]

Originally Posted by mrhasan

Heat sinks are meant to be hot. They taken the heat from the LEDs and dissipate them to the air but not at a rate which makes it run cool (heatsinks have a maximum heat capacity and stays below that or else the heat sink is not the right one for the system). Don't know why yours run cool Probably you are using oversized heat sink?

Ahhh..... wrong

LEDs produce a large amount of heat per area which can seem high because of there size but overall is very little. The junction temperature (between LED and heat sink) needs to be kept relatively cool to insure the LEDs don't overheat, in order to do this the heat sink has to be large enough and kept cool enough to maintain allowable LED temperatures. The cooler the heatsink the better the LEDs work and the longer they last. Most heat sinks probably run around 25-30°C.

[Madreefer]

Originally Posted by mrhasan

Heat sinks are meant to be hot. They taken the heat from the LEDs and dissipate them to the air but not at a rate which makes it run cool (heatsinks have a maximum heat capacity and stays below that or else the heat sink is not the right one for the system). Don't know why yours run cool Probably you are using oversized heat sink?

No just what my fixtures come with.
I've had or still own: Sol Blues, Sol Hydras, Zetlight and Ecoexotic Panorama Pros.
I know how heat sinks work so no explanation needed. Speaking from actual experience rather than something i've read.