Mars Hydro Discussion...

[Yukido]

Hi guys, I just got my Mars Hydro reflector 48x5W yesterday, do I need to put a ventilation inside the tent?

 

[3N1GM4]

Yes, you will need some type of exaust or it will get too hot. Led is much cooler than any other lighting but it still produces heat.

 

[Yukido]

Yes, you will need some type of exaust or it will get too hot. Led is much cooler than any other lighting but it still produces heat.

thank you mate!!

 

[Junk]

How big is your grow space? That light does not throw a lot of heat. Depending on where you are in the world, if you are in a 4'x4' you will be fine. Led's, I've read, also need a different a different set of temps to function optimally. & those temps are warmer.

Unless you have a much smaller tent, heat will most likely be a small issue. But you will need to exchange the air in the grow space regularly just to keep the air in there the right temps & humidity. Unless you are running a sealed system (only reason I see to do that is co2) changing out the air in the grow space will be important.

 

[3N1GM4]

That light does not throw a lot of heat. Depending on where you are in the world, if you are in a 4'x4' you will be fine. Led's, I've read, also need a different a different set of temps to function optimally. & those temps are warmer.

Imo even a small cfl in a fully zipped up tent would eventually overheat if there were no exhaust fan. There is nowhere for the heat to go so it would just build up.

 

[Yukido]

Thank you guys;)

 

[Junk]

OP, how are you defining ventilation?

Imo even a small cfl in a fully zipped up tent would eventually overheat if there were no exhaust fan. There is nowhere for the heat to go so it would just build up.

That light is only 80-100 watts max. It's the equivalent of a regular light bulb in terms of heat, in what appears to be a 4x4 tent.

Convection may work. Open up the top sock & a lower one. Or keep a door open during lights on.

Heat will only build up until lights off. He is going to be opening & closing the tent all the time anyway. I think you are under the impression that light throws more heat than it does.

So, it depends on the size of the tent & the ambient temp of the room etc. I don't know where the tent is, what size (it appears to be a 4x4), what ambient temps are, when he is running his lights, etc.

With that little heat & light, depending on the other factors, the fans he has to run anyway just for air movement will probably cool it enough. If it's in a 4x4, I'm certain he could get away with just fans & if needed, strategically opening up socks in the tent. (I've done it, with much higher heat led's) But I'm assuming by "ventilation" he means intake & exhaust system, ducting etc.

OP, if you are talking about fans, you always need fans to circulate air. Even in a completely sealed system like I have, I have 3 fans going at all times just on the plants. But, unless you have a sealed system running co2, you want the air in the room to be exchanged. This is a separate issue than heat. Available co2 levels inside average like 350 or so? About half of what plants get outside. So if you aren't giving them enough "new" air, you slow their growth. In my opinion, that is what you need to worry about.

Heat build up on such a small scale is not always a bad thing. It can help you reach the temperature differential he wants between lights on & lights off. Because lights off, he will drop back to ambient. Lights on, that thing is barely throwing any heat...so what it does throw, he may want to keep.

The direct answer to his question; does it need ventilation? (& if we are defining "ventilation" the same) I highly doubt it. Open up a lower sock/vent, put a cheap clip fan pushing air out of the top tent sock. For that amount of heat, that would be plenty in my opinion.

If he needs more heat, have the fan blowing out a bottom tent vent. Or just keep something open during lights on.

A cheap fan air exchange system will be plenty. But it's not because of the heat. He has the equivalent of an incandescent light bulb.

 

[3N1GM4]

Each of those 5w leds have an operating temp of around 145° F, a 100w cfl produces much less heat than 20, 5 watt led chips, different lights produce different heat at the same wattage. People think that these led grow lights are just super cool but that isn't true, they put off a good amount of heat. The leds are attached to heatsinks being cooled by fans blowing the heat away from them into the air. If there is no air exchange going on in your tent via a vent fan I am almost 100% positive that your tent will overheat in just a few hours, but I could be wrong.
Plus, you need to exchange the air in a tent anyway to get fresh co2 in.

 

[Junk]

Each of those 5w leds have an operating temp of around 145° F, a 100w cfl produces much less heat than 20, 5 watt led chips, different lights produce different heat at the same wattage.

Correct about the latter. But when I said a regular bulb, I meant a 100w incandescent bulb. But his light, each of those leds is getting less than 2 watts.

People think that these led grow lights are just super cool but that isn't true, they put off a good amount of heat. The leds are attached to heatsinks being cooled by fans blowing the heat away from them into the air.

Exactly buddy! If you are getting into led because you think it's going to cool your tent down, unless you are building it yourself, they dump quite a bit of heat into your tent. I've mentioned swapping out the light below (the 1200) for a cooled 1k HID, my temps went DOWN 4 degrees.

If there is no air exchange going on in your tent via a vent fan I am almost 100% positive that your tent will overheat in just a few hours, but I could be wrong.

You would be. (I'm not trying to be argumentative, I just know for a fact)

Here is mine, that has a 594w actual pull, & I think 240 leds. The tent does not overheat. & I'm sealed with co2 (co2 makes it even hotter)

So, I'll only mention it once more but if that is a 4x4 tent, with just that light, he is not going to need ventilation because of heat...that's they only thing I was trying to clarify. The heat will be fine, I'm absolutely sure of it. I have a light very similar to his, but about 6x hotter. & unless you are in the heat of summer (any light is too hot then) Heat is not going to be a problem. Open up the top sock, & a couple bottom ones and convection will move the air.

Plus, you need to exchange the air in a tent anyway to get fresh co2 in.

That is why he will need some ventilation. But even one simple fan clip fan at the top or bottom (depending on which way gives him the best temps) & an opening large enough for that fan to pull fresh air in will be fine. More is always better, but that is the minimum standard he needs. I think maybe I could have been clearer at the beginning. I wasn't saying he doesn't need to vent the tent at all. I'm trying to clarify for him that his light is not going to produce enough heat that he needs to invest in a ventilation system. In fact, depending on where he lives, & how many plants, pretty soon, he may need more heat.

It's the air he will need to be exchanging. But not because his light is going to be too hot. That light is very small. He needs fresh air in the tent, but he doesn't need anything extensive.

Hope it's all good 3N1GM4. I'm genuinely not trying to be a dick if I'm coming off that way. I'm just trying to clarify for the OP why he needs air movement. It won't be because the light is producing too much heat. It will be for fresh co2. I know because I have the light he has, except mine is the steroid version.

But we are eye to eye on the led heat issue in general. A lot of people switch from HID thinking LED will be cooler. & as you said, that is not necessarily the case. Their are factors to consider like ambient temp outside the tent, whether or not you want to have duct work around etc.

But considering that you need to spend a good chunk of change for an led that will perform to HID standards (the best I've seen anyone do is a $1,000 & the light was practically given to him) I think a lot of people would be better served to run a vented hood with at least a 400 ft3 cfm fan if their grow space allows for it. A 1k hid throws a ton of heat. (I don't know how these people are running 6 DE's in a space) But in a vented hood, with a high cfm fan, much of it is quickly removed. I've not seen a vented LED yet...so any heat they produce, is just dumped right into the space. Is it cooler than & a wide open HID? Depending on wattage, probably. Is it cooler than a properly cooled HID? In my experience, no. One system funnels the heat away from your space...the other one, is just dumping it right into the space. So, weigh all those factors before you make the leap.

 

[3N1GM4]

I have never owned a marshydro light but I do have a 1200 watt cob led by galaxyhydro and that sucker gets HOT. I have a hard time keeping my temp below 90° F in my little tent. I need a tent about twice the size and will have to have one soon or I will have to build a new flower room because the temp near the light, where the canopy will be is just way too hot. I should have researched more before buying my huge light but now I just get a bigger room.:D
Oh and I got my light from ebay for $420.

 

[Junk]

I have never owned a marshydro light but I do have a 1200 watt cob led by galaxyhydro and that sucker gets HOT. I have a hard time keeping my temp below 90° F in my little tent. I need a tent about twice the size and will have to have one soon or I will have to build a new flower room because the temp near the light, where the canopy will be is just way too hot. I should have researched more before buying my huge light but now I just get a bigger room.:D
Oh and I got my light from ebay for $420.

I went to a dual space setup, one flower space, one veg space, for the same issue you were talking about. All I did was make the flower space about 4x the size of the veg tent. 8'x7' I'm sealed though, I don't know what you could get away with if you had a ventilation system.

I like this better because I can start plants whenever I want. Perpetual harvest. Much faster turnover...also, less boring for me.