Upgrading to CMH query

[dougens]

Hi

Beginner here.

I've been running the below kit in a spare room with mixed results:

• 75x75x100cm grow tent
• 2 xCFL 250W
• Desk fan blowing in the tent
• growing in soil - usually 2-3 autos

I have got hold of a 315 Ceramic MH on the cheap and thinking of getting the below as a new set up and starting DWC.
This will be set up in the South of the UK but now have to move the kit to an outside under stairs cupboard, the space is 115x90x200cm - pic here
The space is not in sunlight and in the shade all day.

• 80x80x180cm grow tent
• 315 CMH light
• 4 or 5 inch extraction fan with filter
• 1-2 oxypots (I'll start with 1 to get used to it)
• Nutrients (vege / bloom)
• PH up and down etc
• PH tester

Are there any glaring issues or advice with the new set up?

Will the cool outside air be too cold?
Is the space big enough for the light?
Am I better with a HPS 250W in this space?

I plan to mainly vege and flower at night in case the intake air is too cool with no lights on.
The seasons will effect the temperature so potentially get a small heater for when the lights are switched off?

Any advice, help much appreciated.

Thanks

 

[Humboldtcalikidd]

I’ve got a cmh 315 ina 2x4 tent and it rocks ! The 315 are rated for a 3x3 space

 

[Humboldtcalikidd]

Hi

Beginner here.

I've been running the below kit in a spare room with mixed results:

• 75x75x100cm grow tent
• 2 xCFL 250W
• Desk fan blowing in the tent
• growing in soil - usually 2-3 autos

I have got hold of a 315 Ceramic MH on the cheap and thinking of getting the below as a new set up and starting DWC.
This will be set up in the South of the UK but now have to move the kit to an outside under stairs cupboard, the space is 115x90x200cm - pic here
The space is not in sunlight and in the shade all day.

View attachment 4618312 View attachment 4618314

• 80x80x180cm grow tent
• 315 CMH light
• 4 or 5 inch extraction fan with filter
• 1-2 oxypots (I'll start with 1 to get used to it)
• Nutrients (vege / bloom)
• PH up and down etc
• PH tester

Are there any glaring issues or advice with the new set up?

Will the cool outside air be too cold?
Is the space big enough for the light?
Am I better with a HPS 250W in this space?

I plan to mainly vege and flower at night in case the intake air is too cool with no lights on.
The seasons will effect the temperature so potentially get a small heater for when the lights are switched off?

Any advice, help much appreciated.

Thanks

I run my lights during the day in SoCal and it runs only 8 degrees hotter than the house

 

[dougens]

I’ve got a cmh 315 ina 2x4 tent and it rocks ! The 315 are rated for a 3x3 space

Thanks for your reply.
What's the height of your 2x4 tent?
Is 180cm (5.9ft) enough headroom for the plants with oxypots?

 

[dougens]

I run my lights during the day in SoCal and it runs only 8 degrees hotter than the house

Thanks for reply.

Can you confirm what extraction you use and if 4/5inch extractor is sufficient?

I'm guessing SoCal is in southern califormia?

I'm in the Uk where the winters and summesr are much colder, hence my concern with the cold.......

 

[Renfro]

It's fun to drill through concrete, I assume thats the plan for ventilation?

 

[hotrodharley]

Thanks for your reply.
What's the height of your 2x4 tent?
Is 180cm (5.9ft) enough headroom for the plants with oxypots?

Read up on topping and supercropping. My preferred method. I can keep canopy height less than chest high. There are other methods but I find topping 3 times in a row starting short and then supercropping allows me to shape the plant so it’s open like a wagon wheel.

 

[dougens]

It's fun to drill through concrete, I assume thats the plan for ventilation?

My plan was to cut a hole in the door rather than the concrete!

 

[Renfro]

My plan was to cut a hole in the door rather than the concrete!

I was afraid of that

 

[dougens]

Read up on topping and supercropping. My preferred method. I can keep canopy height less than chest high. There are other methods but I find topping 3 times in a row starting short and then supercropping allows me to shape the plant so it’s open like a wagon wheel.

Thanks for this. I haven't heard of this technique, easy for a newbie?
I'll search the forums for this process

 

[dougens]

I was afraid of that

Why is that an issue please?

 

[Renfro]

Running ducting through a door is just a cluster fuck lol. Can it be done, yeah, will you be happy with it long term probably not. Does it look suspicious, indeed. Is it legal to grow where you are located or is stealth a major concern? A wall vent looks normal on a wall...

 

[Renfro]

If you run accordion duct to the door, make sure to over size it because bends reduce flow. I figure the duct would be moving around when the door is opened / closed and probably not end up straight. I highly recommend sorting out a different solution.

 

[dougens]

If you run accordion duct to the door, make sure to over size it because bends reduce flow. I figure the duct would be moving around when the door is opened / closed and probably not end up straight. I highly recommend sorting out a different solution.

Ah I understand, I didn't think of opening the door! Thanks for flagging that up.

No it's not legal here but the space is completely out of view from any neighbours and in a locked back yard away from sight.

Would it be possible to just leave the ducting in the open space of the cupboard, near the door opening?
The space has a draught from gaps at the base of the door join.

I am wanting a better set up and better yeild / quality but I don't require a lot of product as only for myself on the weekends!

Again thanks for your time and advice

 

[hotrodharley]

Thanks for this. I haven't heard of this technique, easy for a newbie?
I'll search the forums for this process

It’s very easy.

Cannabis Super Cropping: How, When, And Why To Do It - RQS Blog

Super cropping is a cannabis training technique that can deliver huge yields. In this article, we'll teach you everything you need to know about super cropping.

www.royalqueenseeds.com

Supercropping Cannabis for A Higher Yield — Ed Rosenthal

Supercropping is a technique of training your top marijuana plant branches to grow horizontally so that the primary bud is exposed to more light: With more areas exposed, the bud grows larger than normal. Here’s how to do it.

www.edrosenthal.com

I’m literally OCD about topping 3 times. Starting with the third node. Then as soon as possible two more times. You end up with 8 large branches. Wagon wheel it then by supercrop.

 

[Renfro]

Would it be possible to just leave the ducting in the open space of the cupboard, near the door opening?
The space has a draught from gaps at the base of the door join.

As soon as the warmed air exits the duct it will start rising. Very little will make it out of the crack below the door.

 

[dougens]

As soon as the warmed air exits the duct it will start rising. Very little will make it out of the crack below the door.

Thanks for this. I'll get a builder friend of mine to look into a hole in the concrete

 

[dougens]

It’s very easy.

Cannabis Super Cropping: How, When, And Why To Do It - RQS Blog

Super cropping is a cannabis training technique that can deliver huge yields. In this article, we'll teach you everything you need to know about super cropping.

www.royalqueenseeds.com

Supercropping Cannabis for A Higher Yield — Ed Rosenthal

Supercropping is a technique of training your top marijuana plant branches to grow horizontally so that the primary bud is exposed to more light: With more areas exposed, the bud grows larger than normal. Here’s how to do it.

www.edrosenthal.com

I’m literally OCD about topping 3 times. Starting with the third node. Then as soon as possible two more times. You end up with 8 large branches. Wagon wheel it then by supercrop.

Thanks for the links I'll look into this. I always wondered how images I saw on this site of branched out (tree like) plants we're achieved!
Now I know.

Cheers

 

[dougens]

As soon as the warmed air exits the duct it will start rising. Very little will make it out of the crack below the door.

I'm sorry to be an idiot here but the fan intakes air into the tent and the ducting removes the air, is that correct?

I'm looking at this fan.......?

https://www.ebay.co.uk/itm/5-Inch-125mm-Inline-Extractor-Intake-Grow-Room-Fan-Kit-5m-Ducting-2-Duct-Clips/253079696774

 

[Renfro]

I'm sorry to be an idiot here but the fan intakes air into the tent and the ducting removes the air, is that correct?

I'm looking at this fan.......?

https://www.ebay.co.uk/itm/5-Inch-125mm-Inline-Extractor-Intake-Grow-Room-Fan-Kit-5m-Ducting-2-Duct-Clips/253079696774

Generally we use the fan to pull hot air from the top of the tent, with a carbon filter installed on the intake to control odor, the ducting off the fan is then routed outdoors so the heat doesn't get back into the tent. The tent has intake vents in the bottom that air flows into so as to replace the air exhausted by the fan.

I don't have much confidence in the fan you linked, it's an axial flow fan so it's not capable of handling static pressure loss well (duct work, carbon filter, bends). I will tag @coreywebster as he knows more about the various products available where you are located. I recommend vortex VTX series centrifugal blowers here in north america.