New Grow Room - First Timer After Advice

Greetings from Tasmania!

I am a about to embark on grow room adventure! I’ve been researching but would love some more situational advice.

I’ve been busily cleaning stuff out of what I suspect is an old grow room. Next stage is pulling the wall lining off and re-insulating where needed. Then I’ll reline with some spare plasterboard I have laying around and paint the whole lot Flat White. Thinking I will need to put some foam of some sort down on the floor to help with the cold leeching up from the cement floor. As you can see in the pictures below thinks are looking pretty dank and dirty. Until I remove the asbestos lining safely i am not going to be disturbing the dust!

The Stats. The room measures in at 1M Wide x 3M long x 2.4M high. (3’ x 9’ x 7’) Looking at Growing some White Widows in soil.

What would be the optimal number of plants to grow in this space?
What would be the Best Light type to use? LED appeals to me more but if say over winter I needed to run a heater to keep the temps up I should probably run with a MH/HPS setup? The temperatures get towards 0 degrees here over Winter.

At this point I’m thinking 3 plants (First grow) with 2 ViparSpectra 600W LED Lights.

Please let me know the errors of my Noob ways. Any advice is gratefully accepted!

Welcome to ILGM! @SpagMoss

That’s going to be a nice space. You could get quite a few plants in there but you’d have trouble getting to the back to water and end to them due to the solid walls.

You could set up a funnel and hose system to deliver the water to the plants, perhaps.

You need to consider SOG or SCROG. It really all depends on how many plants you “Need”.

I’d probably not go with the foam on the floor unless you build a plywood floor above it? Unless you come up with a way to collect your runoff water it could get down inside that foam and cause you mold issues.

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Excellent point on the mold! I hadn’t thought of that.

There is actually a second double door there that opens more centrally to the long side of the room.

ok cool on the second door. If you are going with Sea of Green (SOG) then you can certainly get 10-12 plants in there easy. Or if you use Screen of Green (SCROG) then probably 6-8 plants would work nicely in that space.

A lot has to do on the lighting you can get as well so as to cover the plants properly. You need 40-50 watts per sq foot of space if you are going to use the entire space or based on what you are gonna use. if you use the entire space

3x9 = 27 1200/27= is 44 watts per sq foot so you should be good on that!

Is that an old wood stove chimney?

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Welcome to [LGM We will help you through your first grow the best we know how that’s what we are here for.
Ya bob31 is correct about the floor…good point bob !
Then there is ventilation how will you bring in fresh air ?
air movement ( Fans )
Seeing how this is your first grow. i would advise you to start small say two or three plants to get started. i’m sending you my link to my journal on Auto-flowering plants and you will see what i have.
I’m sure you’ll have more questions and thats fine we look forward to it.

I will also welcome you to the play ground @SpagMoss
Bob and will have you covered pretty well
If you need advice on ventalation just tag me
And I would start with only a few like @garrigan62 suggested since its your first grow and you’ll have a learning curve as far as your floor goes bob makes a great point I used washing machine over flow trays on my floor of my first homemade grow box worked great for runoff containment just a thought if you can get them locally bro
Happy growing CB

Is the wattage per foot based on actual LED power use or its equivalent to the HPS lighting? Stats on lights say avg consumption 276W (This could be with only one switch on Veg or bloom to impress people with the lower power consumption.) Does say they are equivalent to a HPS 600Watt light… but Im not so trusting of their marketing.

and YES that is a wood heater flu as we call in in Aus. Behind it is also what I can only imagine is a vent hole cut in the wall.

The per sq foot rating is actual draw wattage from the outlet. Most companies will give you both numbers or you can find them online. If you see a 300 watt LED they call it that because it has 100, 3 watt LEDs in it. And yeah I screwed up that calculation. so you’re at more like 25 watts per sq foot. If you’re going to use every sq foot of your grow you may want to add a third light. That would get you real close.

There is a chart in the charts section too that uses the output wattage to determine the distance to use the lights from the plants and I always get that actual draw measure confused with the per sq foot calculation using draw wattage…

So back to your space. The old stove flu has a bucket under it because there is no cap on top of it, correct? So couple thoughts. Put a cap on it and use it to exhaust your grow room. Use it to bring in fresh air. Or cap it, and cover the top or it is going to suck all of the heat out of your grow area if your growing through the winter.

Also the floor is wet in that pic. Is it wet from water running from somewhere else or from the flu? A wet environment might be a problem in the long run


Gotchya. still busily absorbing info about Lights. Not an easy choice while keeping to a budget/first time grow.

Man Bob you are a thinker! I never even considered using it for ventilation! I was planning on removing it!

The floor isn’t wet its just old paint/varnish/evil substance. You are indeed right about the bucket though. The cap blew off awhile back.

I’m a tinkerer so I like a challenge and that little space is a challenge! lol. The thing with the chimney is that if the walls of that pipe got compromised and water is getting inside of it then it is just gonna be a mess if it is left to its own. If the pipe looks solid and water isn’t getting inside the liner of the pipe then the easy way out is to incorporate it into your grow. I’m gonna tag @Countryboyjvd1971 and let him opine as well. He has a certain eye for all things HVAC .

Yeah the lights are a concern. There are so many different kinds and they all bring there different issues with them. I have only grown under t5 and LED so that’s all I pretty much know. I use the t5 to germinate and then I have two inside my tent for side lighting and so that I can work in the tent with the LED off and still see.

If the costs are a concern, decide what you can afford and then calculate your coverage from that. Then you just scale your grow to your lights. Maybe after a grow or two you will be able to add another light or two?

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Since it already there I would put a cap on it outside to prevent rain from getting in I would also put some heavy wire screen around it to keep birds and what not from making a nest in the pipe
I would shorten it up a little and connect my exhaust system up to it
And as far as fresh air intake you’ll want that to be low in room preferably opposite the exhaust for good cross ventilation
passive style vents should be fine if exhaust is sized properly and runs constantly you’ll still need a few fans inside room to move air around
Air flow is key to preventing mold in a humid environment
As far as floor I would level it and then seal it with water proofing or a flex seal type of product
Then I would still use trays underneath to collect run off
I’ll need to do some calculations on cfm requirements for you room size
And bobs right if your on a budget depending on size of light you can determine how many plants you can grow under it you don’t need to fill the whole room up with plants right away

As for lighting, I would suggest that LED’S would be a good idea but my impression after using them is to run a higher wattage than you initially think. In other words, if you were considering a 300 watt, I would double it on general principles. I currently have a 3’ X 5’ X 6’ high grow box and have 2 300 watt and one 1,000 watt. And will probably put another 1,000 watt in.

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@Myfriendis410 that’s a good amount of light
I use 1000 watt cob and two 400 watt cobs in one tent 4x4x7 and 1000w cob with two 300 watt 9 band led in my other tent 4x4x7
Would you keep smaller light in tent also if you added a second 1000 w ?

I think I would go from “1,600 watt” to 2,600 watt with no problems. Heat dissipation has not been a big deal so far. More light just means more sugar production.

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10/4 I just bought my 1000w last grow I used two 400 watt cobs and two 300 9band leds in the same tent
Was nice but wanted better so I picked up the 1000 watt. Cobs for this grow
Hoping it’s plenty I think I will be it’s blinding inside my tents now lol I want to pick up a lumes meter and test output
That’s what I love about leds minimal heat buildup

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I’m with you. I thought those 300 watt were bright then put up a 1,000 watt. Holy cow, batman! To put it in perspective though; 18 inches from the lights is the same level on my light meter as an overcast day outside.

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Out of interest what brands of Lights are you blokes running with?

Also thoughts on 315W Light Emitting Ceramic lights? They are about $800AU each here but notice they are a fair swag cheaper from Amazon.

I’m on the verge of finding out if I get a new higher paying job. If I get it I think I little splurge on some lights will be called for :stuck_out_tongue:

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Nice good luck @SpagMoss with the new job hope it works out for you
I use crxSunny for 1000 watt cob have 2 of them
I have 2 400 watt cob by roleadro Same company as galaxy hydro
And I have 4 300 watt 9band galaxy hydro leds
All have UV and ir all full spectrum

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That’s quite the collection there @Countryboyjvd1971 how are you using them … ie pairing them up flower/ veg ?

1000 w and two 400 in one tent and 1000 and two 300 in other
I use another 300 in my small tent for early veg
So I have three tents two 4x4x7 and one 2x2x4
And it leaves me one as a back up or for seedlings