Check out this old thread there is information on lots of different building methods including the one you mentioned.

Here is a link that might be useful: Brainstorming terrarium thread

Mike thanks for that link, while reading I remembered that I had read that thread before. But after reading some more around here I think I may paint it with patio paint instead of looking for that acrylic stuff that's pretty expensive.

I lined the inside of my aquarium with plastic wrap and sprayed my foam. I plan on taking it out and carving and painting and hoping for results similar to the ones that guy gets.

Hi
Depending on how large your setup is going to be the foam is probably the best. The acrylics are available at HD
but expensive and hard to work with particularly drying times. Another method is to silicone glue variuos materials to the foam after curing. I find painting best as everything I've tried holds way too much water or doesn't adhere well.
Couple of tips. Wear disposable gloves the foam is incredibly sticky!! Use acrylic latex paints. they adhere the best . Don't use two part epoxy paint,causes the foam to soften.
I've been getting the foam for 3.50 a can at WM. Much cheaper than other places.
Good luck with your new setup
gary

Gary,

I got the idea to paint instead of using the silicone from reading some older posts by you I think I will go that route since it's cheaper and easier. Have you ever thought of adding sand or something gritty to achieve a rough bark like texture with the patio paints?

you can add sand. do you plan on ever keeping animals in this, or is it just for plants? If it is for plants then use what you want in it, but for animals there are reasons why we use specific brands of foam and silicone, etc. Otherwise you might be using something toxic.

B2E,

For a while there I thought about having frogs one day but I don't think I'm really a herp person and I don't think I'd give them the best treatment, and what's the point of having something unless you care 100% for it. So I'm going to stay away and only house plants, maybe bugs some day but that's about it. Thanks for the advice I'll keep it in mind incase I think I'll ever change my mind and want to keep animals in it some day.

Hi
IME it is difficult to get the sand to adhere evenly or thick enough to disguise the foam Color choices are limited
and of course some types of sand will release lime. have tried it with fracted glass,crushed garnet and Lapis. Were expensive and short lived.
Coir ,peat,and crushed tree fern will work but I find it's not deep enough to plant and retains way too much water.
Paint was the best all around solution. Obviously you can glue other materials to this.
One tip. You'll find it's really tough painting inside a
glass box ,particularly the corners where the foam is visible from both sides Black jungle uses silicone and puts the foam on top of this.
I make jigs and form the foam outside the box , Then you can carve ,paint glue or whatever in a comfortable chair.
Then silicone the pieces into position within the tank.
Another thing about this method With a putty knife and some care you can remove sections at anytime and then put them back. Really nice with a plant that keeps falling off.
gary

Gary,

Thanks for the tips. But I thought about the carving and painting problems before hand from reading threads here. I lined the fish tank with saran wrap and sprayed in the foam stuff. When it hardened I pulled it out and peeled off the saran wrap from the back and I'm going to use one more can to build it up some before I paint and set it back inside.

hello
Well, you're already an advanced terrarist lol.
have you decided on a color scheme?? i find that growing plants and algae film quickly redecorate anyway so might as well keep it simple. My "Cloud forest waterfall" quickly became "Barely visible background "lol.
On the present setup I used flat black with some turquoise
and gold veins in the water part.On the waterfall area I used some browns to match the real driftwood. it looked so severe that I added a couple shades of green.lol
Probably a waste of time as I'm already getting fantastic growth. Moss and algae are popping up. Also added some refractive acrylic chunks that in direct sun may be a bit gaudy lol. I've always made the backgrounds too colorful and bright and detract from the plants.
gary

Oh I haven't even given a color scheme much thought. And the only part of my terrarium (as of now) that will have a background is one corner where the foam 'tree' I am going to paint is going in.

So far I haven't found many plants I like that have a lot of color so everything is mostly green. I have a small staghorn fern, a pot of strawberry begonias, and some baby's tears. Other than that I guess I'll add plants as I find some I like.