hey glassracks, i used a FeroLED 360 (120 x 3watt) for a space 90 by 45 and got great results ... i reckon you should judge on actual draw and aim about the same as you would on HPS ie 45 watts/ square foot, but thats just me
something of this size light would probably cover 2 x 4 just as easily, but I wouldnt push it any further. I think you have to be careful about the areas covered by LEDs, manufacturers seem to claim huge spaces. I may be being old fashioned about the watts/sq foot thing but who really wants to finish a crop with not enough light? (mind you you do have the original lighting there too).
Also I noticed a huge diff when I switched my original light for the 4G 360 version which has 3 watt diodes and deeper penetration ...
FeroLED did sponser my trial grow (you can read the grow reports
here) but I have no affliation with them .. what I would say is that their light performed great, seems to be of solid build, their prices seem good and they give a 5 year guarrantee ... so when you ask for tips on brands, I'd say include them in your list
Other points I'd say are:
I found growing with LEDs overwatering a problem I'd never had before .. due to lack of heat the plants transpire less I guess ... and I'd recommend growing in a soiless medium such as coco-perlite mix. This gives you the control of a semi-hydroponic grow and the flexibility of using pots. Also you need to watch out for signs of mag & calcium deficiency (particularly if you also use the coco-perlite method). Where i live there are high levels of calcium in the water, so I just add a spoon of epsom salts (magnesium sulphate powder) once a week to the watering.
Yes, keep the pots off ground level. I just use folded crates.
ps there are some more tips on growing with leds on my blog .. look for a post called "quick guide to growing under LEDs". I'm no expert on them ... its just a few things I found whilst doing this grow.
Peace and happy growing
