Light help in vivarium!

[getyaya]

Hello :

I'm new in the forum, but i have a few years in the cultivation of orchids. For some time here , I have several obsession with some genres , which they resist me .
Whereupon, I decided to make a terrarium for cold climate orchids .
I would cultivate genres: masdes, draculas, dendros ...

I have mounted the structure, which is 1.2 m high x 1 m long x 0.7 wide.
My problem to decide, after many readings, is the choice of the light.
I have two options :
-3 Of 39w T5HO ( silvania grolux , G5 or T5 FHO 39W/865 Luxline Plus)
- Led

The first option has the advantage of ease of installation and replacements , but the downside of extra spending instead of tubes and the power bill.
The led, in their favor have a higher light output and a greater life span.

Becouse this money saving and other advantages in terms of the choice of the ranges of light, I think the best would make me a dIY Led.

Someone could help me realize the watts and lumens range necessary for my case?

There is not much information about LED and orchids , I build on aquarium forums , reaching the conclusion that my measurements are equivalent (more or less)to a 120 liter aquarium . They use about 90 watts.

Hopefully come to a good end in this adventure .

Thanks in advantage