[leo92]

hi everybody thanks for your help! i had a growroom 50cm x 60cm and height 1,20 m. I think a 105 watt led lights should be ok, i will use 2 different red (620-630 , 660-670nm) and 2 different blue (445-450 ,460-465nm) and maybe some white led 3000k lights. the led are 3 watt each so the will be 35 leds.
now the question is how many red leds, and how many blue leds?? and should i use whit led?? and what about uv and ir leds??

[VladTheInhaler]

1. By all means use some kind of white.
2. Some people use 660 nm reds some use 630's, according to some to much 660's can have negative efects on plant growth, depending on genetics (of the plant, not your own)
3.generally people have been getting good results by mixing red:white:royal blue in ratio 8:3:1 or something similar. EVO series led lights were made by using only cool white and red Cree xp-e (I think its xpe) in ratio 6 reds and 3 cool whites, because cool whites have nice spike in blue.

You do not mention the current you want to drive your leds on, wich is more relevant info as to what wattage you will pull out of those leds.
Generally speaking, at your cab surface 70-90 watts of leds should work fine.

There's quite a number of threads covering DIY led construction, do yourself a favor and read them before you pull the trigger.

[vukman]

There are different schools of thought but the one 'rule' which seems to run through all of them is the need for white light..IMO, white light is a must. Now, here comes the different thoughts...NW, CW, WW....that is up to you.

Also with the reds..some say 630 only and 660 decreases growth, some say 630 and 660 but 660 only during mid-flowering. Others say 660 to 680 plus an IR for the "Emmerson Effect"

The same applies to UV. It is generally, more or less, proven that UVB contributes to more THC forming on the buds to protect the 'seed' (in our case, no seed/s) ...(1) UVA is suppose to help with pests...

Different schools of thought as I said.. Personally, the perfect ratio/spectrum doesn't really exist because there are too many other variables involved. You can have two exactly identical grows and set ups and yet, one might be better than the other....Why? Genetics, 1ml of something different, soil mixed twice more in one than the other..etc..etc.. I think you get my point....

Just keep reading everything, absorb what is useful. Sooner or later if you want to DIY, you just have to settle on something and take the plunge.

(1) https://www.hempfood.com/iha/iha01201.html

Good Luck