not enought lumens

hello to everyone. i read that i need to get 7k lumens per square of feet. so i measured my grow space and its like 3 square of feet large. so those would be 21k lumens. i actually dont know how to get so many of them, so i need info: how do you get so many lumens with cfls? i cant understand it, i have seen in a lot of diaries, that people often use really small amounts of those cfls lights but anyway their final yield is pretty good. thanks

You can pick up lumens at grow shops and places like Home Depot... they are about $2.00 each.


Just kidding, if I were you I would look into a 400w-600w HPS system for flowering in that space.

GrowTech said:

You can pick up lumens at grow shops and places like Home Depot... they are about $2.00 each.


Just kidding, if I were you I would look into a 400w-600w HPS system for flowering in that space.

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and how much do you pay every month for electricity used by that light?
anyway, i would like to hear what CFL growers say..

sorry for my english

Not sure if it is correct information, but read the lumen output per light bulb on the CFL package. They usually range from 1400-1650 lumens per bulb. Just add the the bulbs and lumens up to what you need. That's what I did.

You don't HAVE to use all of that space

Use a tall cardboard box or something

for a 400 watt with ballast (apx 460w) at 10c a kilowatt itll be 19.87 in flower and 29.81 in veg! hope this helps! its from a book i got at my hydro store

A 150w hps gives 16000 lumens. One of those is easy to cool, especially if you remote ballast. You could use one of those and a few supplementary cfl's or two 150's with DIY cooltubes.

CFL's would take too many to equal that number of lumens as you have found out. You could grow with less, but then you get really light fluffy little buds and end up paying just as much for electricity as if you had a couple little hps's. Add up all the watts on all the little cfl's you would have to run and it'll become clear pretty fast that HPS makes the most sense.

Either that or a pulse start halide, those are good for veg or flower, make less heat than HPS (only by a little) and are available in 320w size with just the right lumens you want, at around $80 shipped.

Electricity consumption cost formula:

W x T x P = _xxx_ Divided by 1000 = $__per day. (Just multiply the $__per day to how many days in the certain month)

W=Your Total wattage in use. (ex. 400watt-HPS)
T=Total hours used per day (ex. 18hours veg or 12hours flower)
P=Your cost per Kilowatt hour. (ex. Mine costs $.10 per Kilowatt hour)

Hopefully this makes some sort of sense.

AnneH said:

You don't HAVE to use all of that space

Use a tall cardboard box or something

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why would u suggest something like a cardboard box??? seriously.
CFLs work fine, u dont have to use HPS like everyone says. for those who stand by their HPS, check out DR.BUD's grow with CFLs because hes doin just fine and producing extremely large buds in plastic bottles. not everyone can afford HPS

Lumens can be calculated by looking at the label on your CFL product. The general rule of thumb for CFLs are 60 (to 70) lumens per watt.

For example,
a 42watt CFL x 60 lumens/watt = 2520 Lumens per 42 watt bulb.
a 23watt CFL x 60 lumens/watt = 1380 Lumens per 23 watt bulb.
Just keep adding bulbs until you reach your desired lumen output...