Need input re: flouro lighting

artemisinked

Active Member
I sprung for a 400w HPS to grow in a closed off cedar closet in the basement. I wish I could say I knew more about DIY construction than I do, but I'm a girlie chick. Anyway, light is too hot, there's little way for me to properly vent, security is an issue as the light is visible if the door is open, and this whole thing is clearly a potential firehazard so I need to get on working out a plan B. I'm not too keen on burning down my house and the rest of my suburban block.

I have another seedling set up with 2 20W cool flourescent tubes that I got from a gardening catalogue that I use for all veggie seed starting and they work fine on getting the MJ seeds up and going. I'd like to abandon the HPS and try this with flouros as it's probably safer.

Question is: What additional flouros would I need to supplement a 6 plant grow (3 Joint Doctor autoflower dwarves and 3 regular indicas)?

Many thanks in advance for stupid newbie that doesn't want to burst into flames. :-?
 

moneymakerwa

Active Member
although I am sort of new to the scene... factors such as how tall/big do you want them should be considered. the typical conversion with hps lights is 35-50 watts per square feet of growing.. so I would imagine it would be relatively the same. Id be on the higher side because hps has a higher lumens per watt rate.
 

Smokey.Mc.Pot

Well-Known Member
if you wanna use cfls for 6 plants, id say 2 fluros per plant untill they get bigger, then you can add as many as you like.
 

stoverdro

Well-Known Member
Alright...well first off youc an make the hps work if oyu really want to rather than investing more money on lights that wont do as good as the hps. Do oyu have a hood with it correct? Well maybe look into upgrading to a air coolable hood and hooking an inline fan up to it venting the hot air right at the source(bulb) to the outside of your grow room. And exactly how big is the room?????
if you dont want to do that look into t5 lighting. Its flourescent but its like the shop lights. I would get a 4 foot 4 bulb fixture unless you can afford the 6 bulb one. it is 4 feet long and about 2 ft wide. thus making it so you can fit 6 plants in there and it will give oyu the best light you can and maybe add your existing flouros to it also but that is un needed. it puts out with the 4 ft bulbs 4000 lumens per bulb and with 6 bulbs that would be 24000 lumens.which is pretty damn good ya know. and it would be cool and closer to your plants. then you can get the 2 types of bulbs one set of 6 being grow for the vegging stage and the other 6 bloom for flowering stage. look em up on ebay they run from various prices.
 

artemisinked

Active Member
I was planning to supplement the 2 24" 20w fluorescents that I have for seedling starting already with CFLs because I thought that might be the easiest at this point. I have no way to vent that stupid cedar closet without light leakage that will most definitely be visible outside the basement windows from the street. Talk about obvious- and there's a state trooper that lives a mile up the way.

Can you guys comment on the following- keeping in mind that of the 6 plants, not all will be female so some will have to go:

For vegging:
2 20w cool white fluoros (3430 lumens)
2 65w cool white CFLs (8400 lumens)

For flowering:
2 20w cool white fluoros (3430 lumens)
replace cool white with warm white CFLs- 2 55w CFLs (7200 lumens)

I'm aware that the more light the better, but I also need to keep in mind that all the lights are on one circuit so I was hoping to supplement the 20w tubes with only 2 CFLs at a time. Is this still too little light for a half decent grow?
 

BongJuice

Well-Known Member
It is definitely possible to grow with fluoro's. But your plants will look like shit, and when it's all said and done you'll wish you went with more lighting.

I understand from your situation it's not possible with light leakage to vent.
But if you can't vent the room. You might as well pack it up, and call it quits. The room needs to be vented.
Plant's need ample enough atmospheric CO2 to grow, and they'll be exhausting oxygen. It will get way too humid in there. You need some way to exhaust that stale air, your plants will die eventually if you don't.

You could get a T5 light fixture. T5 bulbs put out more lumens, but don't use as much energy.

Think of it this way, try to make your plants think they are outside.
What would you do?

Growing with 40 watt fluoro's is the same as growing on an extremely cloudy day.....everyday.
No venting would be like sticking an aquarium upside down over your plants.......They need air.....and lot's of it. Plus they need the old air to be exhausted from the room.

Cannabis needs 3 things to bud. You can grow the plants, but you'll never get bud without these 3 things.

Lot's of light
Lot's of fresh air
and lot's of clean water.

You take one of these away, your plants will die.

It's that simple.
 

Kludge

Well-Known Member
Well I too am something of a newb, only been growing for about half a year, but this is what they say:

"The sun provides 10,000 lumen per square foot; when growing indoors you should strive to provide at least 5,000 per sqft." - They

One thing to keep in mind is that the intensity of your light is an inverse square of the distance the plant is from the light (L/r^2). Light doesn't follow nice tight lines but we can just pretend it does for simplicity's sake when figuring out our light intensities.

So for instance:
Currently I'm using a 600W outputting 95,0000 lumen and covering 9 sqft; I have the tops of the plants at about 6 inches from the plants. Using our handy dandy calculation we see that at the top the plants are getting 95,000L / 6in * 6in = 2639 lumen per square inch = 31,668 lumen per square foot. And very bottoms are getting 95,000L / 3f * 3f = 10,555.

Now for your situation we need to figure it backwards. We're going to say you want half of the recommended light at the surface of the plant so that would mean you need 208 Lumen per square inch (2,500 / 12). Now assume your plants are covering 9 square inches each; L = L / 1 = 208 * 1 = 208 lumen per square inch = 2,496 lumen per square foot

So, for a really, really weak plant that won't grow anything below its canopy you will need at least 2,500 lumen and you should be able to get that in two 23W bulbs but I would suggest at least 3.
 

artemisinked

Active Member
This is completely fantastic input, thanks so much guys. Actually, if I'm using the fluorescent seedling light and the 2-3 CFLs I don't really need to grow in the cedar closet. I can easily do it in another portion of the house so venting is not an issue because there is appropriate air circulation via fan and central a/c. SO, if I can get a sufficient number of lumens for what I assume will ultimately be 2-3 plants, then I *might* be okay because I only need for personal consumption.

Will LST assist in ensuring that the plant is exposed to more light? I was thinking that this might help, but could use some feedback.
 

artemisinked

Active Member
Oh yes, I should add that I'm planning on keeping them fairly small- (3 of them are dwarves anyway)- no more than 24 inches tall, and likely will LST. Does this change your opinions?

Again, I can't thank you all enough- obviously new at this so your thoughts are appreciated.
 

Kludge

Well-Known Member
LST is a great way of getting more usable light to your plant. I've used it in to lift sagging branches and to pull branches out to a spot where they don't compete for light. Sounds like a good plan.

You're still not going to get a whole lot out of it but as long as you enjoy the process that's all that maters. Light = energy = more bud.

Using the 1 gram per watt for HPS and converting to lumen and accounting for conditions I would guess that using 3 CFL's of about 1750 lumen you could grow about 10g off one plant. A really talented grower with years of experience and a perfect grow room could get a lot more out of it of course (theoretically up to about 35g), but that's the optimal condition. Someone like Garden Gnome could do that much off a few little lights; and probably has.
 

Kludge

Well-Known Member
Oh yes, I should add that I'm planning on keeping them fairly small- (3 of them are dwarves anyway)- no more than 24 inches tall...
24 inches is HUGE for indoors.

This plant is only about 15 inches tall and should give me about 40g dried (still drying at the moment so not totally sure).


And these plants are now about 18 inches tall and should give me at least an ounce each on average when I harvest them this week:







So you see 24 inches is really, really big for your grow conditions. You want to keep yours at about a foot or smaller.
 

artemisinked

Active Member
HUGELY helpful! Wow, folks, you rule. Props given post haste.

Amazing plants, Kludge. I will keep them short per your advice. I don't need much, but am a med user so want to see if I can capitalize on some strains better suited for pain relief.
 

stoverdro

Well-Known Member
if oyur looking at strains for medicinal usage i have heard good things abotu white rhino and have also heard there yields are good to....just a suggestion for future references.
 

Kludge

Well-Known Member
HUGELY helpful! Wow, folks, you rule. Props given post haste.

Amazing plants, Kludge. I will keep them short per your advice. I don't need much, but am a med user so want to see if I can capitalize on some strains better suited for pain relief.
Thanks. =)

I don't know enough about strains to give any good advice but what I've been doing is reading the Big Book of Buds to learn what the different strains are.

P.S. Oh, here's a 24 inch plant; it's a White Widow week 2 of flowering.




.
 

Rollbilly

Active Member
Why can you not put blackout curtains against the basement window?? Why not buy a blackout curtain twice as wide as the closet in the basement, put from above the door and vent leaving the door ajar?
If you move your plants to an open grow area (ie:- no closet. ) You will be losing loads of light as it spreads around the open space. The very reason for using closets or small areas is to contain the light.
And buy a fan, anything will do, just a small fan to keep the air circulating, pc fans are often suggested so you can gather it does not need to be powerfull.
Good luck with your grow, looks good so far, I would be happy with what you have grown.
 
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