Grow light (LED)

[HTLOKS]

Hello there!

I was wondering if i could get an opinion from you guys regarding the usefulness of this ufo leds, i'm planning on growing a plant, in a 40x40 enclosed container, I've got everything covered, except the lighting part, I was thinking on buying this type of ufo led (link below) but I'm not so sure about it's effectiveness, could you help me ?


https://www.amazon.co.uk/Derlight-V...qid=1483051842&sr=8-1&keywords=derlight®+150w


https://www.amazon.co.uk/Roleadro-F...&qid=1483051895&sr=8-1&keywords=Roleadro+138w

https://www.amazon.co.uk/KJLARS-Pla...F8&qid=1483051922&sr=8-1&keywords=KJLARS+150w

 

[Phaeton]

One of the problems with any point source of light is the shadowing. Having all the light from a small area causes the top leaves to put the leaves under them in shadow unless the light is moving across the sky.

The easiest fix is to use two or more lights offset about twenty degrees from center, not a stadium grow but similar in principle, the light goes down the sides of the plant. This puts a great deal more energy into the leaf surfaces.

Another problem is the round shape makes a hot spot in the center, a rectangular light at least makes the hot spot wider so a a pair, one on each side, covers more of the plant with the 'sweet spot'.

The three links are all for UFO's in the 50 watt range, suitable for a 15" x 15" enclosure. I automatically assumed inches and was about to call the light too small. Being American I am like that, but if it is 40 cm x 40 cm then the light is about perfectly sized.