"TANK" DESIGN QUESTIONS??

[CALLY]

Hi,

I'm a newbie to the site.

I am building an orchidarium in the holidays an am looking for some finer details.
I live in JHB, South Africa and we have very hot summers and very cold, dry winters and my orchids hate this varying temperature.

My orchids range from a Vanda, Odontoglossums to Phals and have a few questions:

1. Lighting: LED's or Florescents?
I have tracked down some new LED's that have the specific blue and red frequency that is required for photosynthesis and flowering. They deal with the humidity and moisture better than flourescents.

How do you calculate how many lights you will need?
The Orchidarium is 1.2m high by 1m long by 600 wide with a 200mm egg grate shelf half way up.

2. Temperature control:
A ceramic reptile heater caught my attention and can also deal with the humidity. Where would be the best place to place it ?

3. Humidity:
There is a humidity tray under the case and the bottom of the case is an egg grate shelf. But my Vanda needs considerably higher humidity than a humidity tray can provide. So is a normal room humidifier eg Carmen modified going to be enough for the space ?

I've also heard of a fish tank heater being quite effective?

You can get a reptile fogger, how do you calculate if it will provide enough humidity before buying it?

4. I have one normal computer fan placed in the middle of the back wall. Will this be sufficient?

5. The different requirements of the orchids like odontoglossums like it a bit cooler, but can i grow them all in the same case?

Any suggestions will help.

Thanks