What's new
  • Happy Birthday ICMag! Been 20 years since Gypsy Nirvana created the forum! We are celebrating with a 4/20 Giveaway and by launching a new Patreon tier called "420club". You can read more here.
  • Important notice: ICMag's T.O.U. has been updated. Please review it here. For your convenience, it is also available in the main forum menu, under 'Quick Links"!

I want to vertically hang a MH/HPS bulb in my tent in the middle of my plants at plant base height

Ca++

Well-known member
I'm not sure a 1.2 tent ever needs a 200mm extractor.

This garage attached to the house, so you can put a vent through?
 

delta9nxs

No Jive Productions
Veteran
your 760 watt light only needs 1528 btu cooling while running so a small exhaust fan directly over the light would be fine. i'm thinking something like this:
https://www.homedepot.com/s/duct%20fans?NCNI-5

i linked all of them because the page is hilarious, but the little 4" will probably be enough for that size space. i have been running these things for years and they are very reliable.

i found the page funny as they show the same fans for hvac, growrooms, and tents! looks like they're finally figuring out the market.

so, basically, you have 2 choices, sealed or open. each presents challenges. if you run an exhaust fan what happens when your garage gets cold. will a little heater offset your winter conditions?

to be perfectly honest, i have been a stealth, black-market grower for most of my 25 year career.

i have become adept at modifying household heating and cooling systems to make all kinds of weird situations work.

if you do hook up the ac you will have to run co2.

i used to be religiously addicted to co2 supplementation but a house with people and pets can produce significant co2.

it is consumed on a per unit basis so as long as you don't let the co2 level fall below about 400 ppm you'll be fine.

your house has a system installed already. is the house attached? if not, forget all this but if it is you can easily run a small duct like a 4" flexible one.

i have crawled under a rental house and connected an 8" flex duct to the main duct using the right gear so that later if anyone finds it they will think it's been there a while. then ran it through a wall and hidden in the garage by a cabinet that was next to the grow room. this was a 10x30 ft room with ten huge trees and hps lights dropped between them.
 
Last edited:

Roadblock

Active member
If worried about heat Id put it in a cool tube and extract air straight up the tube, Im thinking about doing it myself I run 8 plants in a 10x10 and have room for a verticle light when I push them out from the center, mine are on little trolleys with a draining tray and net over the plant so they are self-contained so I can move them around the room.
 

Ca++

Well-known member
I have a switch on the floor, for my floor lights. Being LED, it's easy to flick them on and off. You can't do that with discharge lighting though.

I often find myself wishing I had done more about dimming the lights.
 

Three Berries

Active member
Those inline fan are quite inefficient when compared to variable speed EC motor axial fans.

There are swamp coolers that also add humidification, some easy to make if you have skills.. Peltier coolers too but they get expensive.

I would like to use water myself somehow.
 

Switcher56

Comfortably numb!
I have a 760 true watt 3200 samsung diode full spectrum 8 bar overhead dimmable LED light and a master controller to go in a 48x48x72 tent. I have not run this light long enough to see how hot it gets, but my guess is this LED at full power puts out a bit of heat. I will have it auto dim at extremely high temps. Im thinking 4-6 plants per grow.

I will only be growing during winter and colder months PNW and it will be in my garage which is not well insulated. I figured i could throw in a cmh/mh/hps bulb and create heat that way for the right temps but maybe i should skip this idea and just use a space heater??? I believe my current overhead lighting is more than sufficient for a 48x48 room
You can also throttle your exhaust fan during lights out... or buy an Infinity fan that will do it automatically based on temp. The Q is, what are you trying to achieve? Deal with the issue vice trying to combine things that never really fix anything. IOW you are chasing your tail. You can have drop down lights, they don't have to be HPS/CMH (which run hot). You need to control the temp not the luminosity, in order to affect the tent temp. Besides, the glow of HPS/CMH (read heat) that close to the plants might be detrimental. It is akin as having your plants to close to the light.
 

Three Berries

Active member
If the temps are too high it really takes a lot of air flow to bring it down. Air isn't that good of a thermal sink. You end up really lowering the humidity. In tents anyway. A open room would be easier to manage I would guess.

But you can us the humidity to help out as the more humid the air the more heat it can hold as the water vapor expands more than the air and increase percentage wise. So the exhausting becomes more efficient with less air flow.
 

dlxtpnuo

Active member
I am running an overhead LED setup that is good...... but for more lighting and to increase temps which will help me a lot I want to use a 250-600w MH HPS bulb and ballast. I dont want a reflector, I just want a digital mh hps ballast with a cord that leads to a connection that takes a mh/hps bulb. I just want the bulb dangling from the top of my grow tent in between the center of all my plants at plant base level. I want 360 degrees of light from this.

I cant seem to find anything like this online. can someone point me in the right direction? Also the less wattage the better with this light.

thank you sorry for my naivety

Hi fellow cannabis enthusiast. Working with MH & HPS requires a great deal of experience. I personally do not agree with the dangerous concept of grow tents with MH & HPS. When this was a new consumer concept around the millenium (2000), things like water cooled lamp housings for MH & HPS lights extracted the heat making so-called MH & HPS tent grow ops viable. Since then the media and home growop supply businesses have continually dummed-down the many dangers like the intense heat and high voltages.

LED's on the other hand are fairly safe and simple in comparison. In short MH & HPS produce intense heat, and typically need many metres of clearance depending on the wattage. Any item too near will simply heat up and combust. LED's on the other hand are fairly cool, with only basic precautions required, and a tent for LED's should be fine.

It is going to cost a lot more to recover the damage caused by a MH & HPS fire. Even the inevitable damage caused to cannabis vegetation by mistakes with the intense heat is not recoverable and your seeds plus much work will be wasted. So why not invest in LED's. An investment in LED's now could save money in the long term, whilst virtually guaranteeing a cannabis crop. Plenty of second hand LED's are being sold on websites like Ebay for small amounts of money. Many are fully integrated, very reliable and are great lights to use. On Ebay use search words: LED GROW LIGHTS, (VIPARSPECTRA) (in hydroponics).

Here's a quick look at the realities the intense heat of MH & HPS can cause.​

Firefighters battling a Cambs house fire discover it's a cannabis factory
housefire.jpg


0_Cambs-Police-cannabis-house-1.jpg


The fire started in a room with cannabis plants (Image: Cambridgeshire Police)

A fire at a cannabis-producing house in Cambridgeshire could have had ‘devastating’ results, police said today (June 22 2021).

The fire service was called to a house fire in Little Downham, East Cambridgeshire on Sunday, June 20.

While extinguishing the flames in a bedroom on Lawn Lane, they discovered the house was being used to produce cannabis on a large scale, and alerted police.

A 55-year-old man was arrested on suspicion of cultivating cannabis, after around 40 plants and growing equipment were seized.


A drug-growing operation was discovered inside the house

A drug-growing operation was discovered inside the house (Image: Cambridgeshire Police)
He has since been released under investigation.

Cambridgeshire Police said: “Some might think it’s 'only a plant' but drug dealing and cultivation can have a devastating impact on communities, and this cannabis factory in Little Downham nearly caused a devastating fire”.

Photos from the scene on Sunday show damage caused to a first-floor room containing cannabis plants, with many more being farmed in other parts of the house.

Sharing the incident on social media, the force directed people to report any suspicions of drugs being grown in a nearby property, through the constabulary’s website.

Cambridgeshire Fire & Rescue Service has been contacted for comment.

Link to this 100% genuine news article: https://www.cambridge-news.co.uk/news/local-news/firefighters-battling-cambs-house-fire-20878012
 

Roadblock

Active member
I second the eye damage it is really bad without sunglasses
I just hung a 600 vertical last night and now I cant look anywhere without getting blinded by it, seems a peak hat wont cut the light now, the added vertical looks to have made a big difference in whats lit up, it will probably contribute to yield more than any light in the room, first time Ive had vertical and will be interesting to see the result.
 

delta9nxs

No Jive Productions
Veteran
1656768221117.png



this image is a stock photo appearing in literally hundreds of unrelated articles:

https://www.google.com/search?tbs=s...WUKCfA4HhDy0wN6BAgBEEE&biw=1366&bih=625&dpr=1

further, although there was a house fire in cambridge, uk in a house that contained cannabis, there is absolutely no mention whatsoever of the cause and nowhere is there a suggestion that hid bulbs were responsible for it.

it was most likely overloaded circuits caused by the cannabis grow but that is a lot different than inferring hid bulbs caused the fire.

also, bringing this kind of "fake" public safety article to icmag is so ludicrous. do you think you are talking to teenagers trying to grow in their mom's closet?

this is the most prestigious cannabis mag on the web today and it is full of world-class growers.

these kinds of articles are bad for cannabis. tell the truth!

i want to add that this entire article written by dlxpnuo appears to be an attempt to sell led lights. i wonder if he is a vendor?
 
Last edited:

Cerathule

Active member
I just hung a 600 vertical last night and now I cant look anywhere without getting blinded by it, seems a peak hat wont cut the light now, the added vertical looks to have made a big difference in whats lit up, it will probably contribute to yield more than any light in the room, first time Ive had vertical and will be interesting to see the result.
Nice, what other lights are in there? You mind sharing a pic?
I think it's good advice to always put some glasses on when opening a tent or growroom, also the LEDs will emit a high irradiance. Our eyes quickly throttle that down but that doesn't make it less heavy on some of our eyes tissue.
 

herbgreen

Active member
Veteran
Depends how long you need to be in there

LEds will boggle your eyes and maybe your mind

Use a supplemental T-5...let that be the light while working

Turn the heavy lights back on when you leave
 

herbgreen

Active member
Veteran
Going Vertical is the same deal...stay out of there when its on

Use T-5 as "worklights"




 
Last edited:

herbgreen

Active member
Veteran
The 315s have the extra layer of tempered glass that regular MH/ HPS does not

Which may or may not offer any real protection from heat induced fire risk

If ever in doubt ... have an electrician look into it...Electricians get high too!

Its an overload of the panel somehow And probably not a light bulb causing fires

Its all UL stuff these days

Dont overload your tent with wattage!:rasta:
 
There's some really great threads in the ol vert section. Besides Marlo, Ichabod is full of vert knowledge.

He switched to led panels here, but really in depth knowledge on vertical growing.

And @DHF is a treasure trove of bare bulb lessons.

I kept looking for dimmable 315 CMH with remote ballasts for my setup, but couldn't find any. Ran 2 stacked 315's in a 3x4 footprint with 7' ceilings. Heat was a bit much in summer, so switched the bottom bulb to a corn cob led. Really helped with heat and was easier on my eyes.

I ran a dimmable 400 hps in a pretty small space for a couple years. In certain situations, vert is the way to go
 
Top