Making A Waterfall

[piper]

Right my idea is to make a small waterfall in my 265L tank.

Originally I was going to create this out of polystyrene, covered in cement then sealed. I'm concerned however that the roots of my plants will eventually break through the concrete allowing it to leach nasties in to my fish's water.

So I'm now thinking of using Lava rock, from what I have seen it seems very light and looks easy to cut. But is it too light to sink. Has anyone used this rock before?

 

[Gazoo]

Lava rock from LFS's that I'm familiar with is relatively light compared to other rocks but it definately sinks. It is also inert (like slate) and should not change your water chemistry.

I used to have a collection of it in my tank but recently switched over to mopani wood.

 

[touchofnature]

helo Have you looked at any or did a seach for DIY Background. I got some good things off ather peoples sites. Have not came acrossed any lava rock backgrounds . Good luck

 

[Tcian]

My LFS has a pond display with a ceiling high waterfall and background made out of lave rock and mortar, mounted to cement board with 2X4 framing. He uses plastic plants set into the mortar to break up the waterfall and the lava rock extends into the bottom of the pond. Very cool looking set up! He picked up the lava rock from a local landscape supply store and did the whole thing for under $200.