Waterfall materials

[bobgildolf]

Hi y'all. I've been building my WTF's new viv and I have now come to the waterfall feature. I have used expanding foam to make the waterfall shape and now I want to use a cement type product to cover it with. I've seen this done in vivs on google images and I it looks really good.
I'm sure normal building cement contains lime, which is obviously no good.
Does anyone know anything about the safe stuff which they are using in these setups?

[Tom Highum]

I have heard quickrete is fine. But you have to cure it but don't go on my word.

[SludgeMunkey]

Tapecrete is best, if you can get it. It is rare and expensive here in the States as it is made in India. It appears it is easier to get in the UK though.

While I know nothing of brand names available in the UK, I use Quickcrete brand cement and their acrylic fortifier. The acrylic fortifier is a necessity if you plan to use any concrete in a vivarium as it makes it 100 percent water proof. Skip mixing in water; use the acrylic fortifier straight out of the bottle. It is better to brush it on in many thin coats over time rather than one thick coat. Mix only what you can use in 10 minutes per batch. You must allow a minimum of 24 hours curing time between coats. Once all your coats are complete, you must allow a minimum three week cure time in a humid environment. If you do not allow for proper cure time the concrete will crack and crumble.

One note though: Expanding foam does not make a suitable base for concrete based constructions. It shrinks and swells over time and will crack the concrete. If you do want to use the expanding foam as a base, just remember it will require a minimum cure time of a month in a warm, humid environment or it WILL fail on you in a very short period of time.

I have a few threads on here featuring projects in progress with this stuff. I have one in particular on Caudat.org (search for "Okinawa Project"). Also on Caudata is a user by the handle of "grius" He is the master of concrete use for vivaria and taught me how to make it work. My projects are absolutely nothing compared to his museum display quality builds.

[winyfrog]

I used the foam to build my stream and waterfall. to cover it I just took black silicone and stuck some gravel to it this makes it look very natural.

[Tom Highum]

Looks better in my opinion if you mix sand and silicon together and use multiple colors of silicon

[bobgildolf]

Hey, thanks for the input. I think I'll save the concrete idea for my next project. I have started to silicone earth/coco fiber type substrate to the background. (what a mission!!) I was going to do the same thing with the waterfall but now I like the sound of Toms idea. I have been using aquarium silicone, but at around £10 for a tiny tube it could get a little expensive for my wallet. The only black silicone that I can find is alot better value for money, but says it is not safe for aquarium use.
Are you using a special type of black silicone?