drainage
 

As an absolute beginner, I have a very basic and fundamental question: should a terrarium have drainage holes in the bottom? Won't the water stagnate in the base layer (I'm planning to use expanded clay balls "hydroton" and install a small fan for circulation).
Also, with regard to terrestrial orchids, can they be planted directly into the substrate - or is it best to place them in plastic pots, which can then be disguised with sphagnum.

Re: drainage
 

Yes, Sydney. Drainage is a must, unless you're extremely careful with watering. I use a couple of inches of clay pebbles for drainage, then do plants on top of it.

This tank, I used pea gravel as it was cheaper ;)

Click Here

thanks for that Marty...so you mean to say actually I need to have holes drilled into the bottom of my glass terrarium (an old recycled fishtank), or will a good layer of clay pebbles do the job of drainage.
What do u use a s substrate?

I use both methods. I have some acrylic tanks with clay pebbles and with drainage holes and I have a 90gal fish tank that is not drained, but it has pea gravel at the bottom. I periodically have to drain it manually by siphoning out the water.

Marty,
do any of yours have water features using a pump? I like the idea of having a water feature with a pump but the possibility of it clogging up or breaking down and needing to access it is a problem.

Using a cannister filter would solve that but if you have a 3ft tank turned on it's end and converted into a vertical viv it would have to be an extremely powerful one to be able to suck water up the 3ft and over the back of the tank and then pump it back and over again :hmm