Marina 3D Styro Background

[jred]

So this week I was able to snag some 3D background pieces manufactured by Marina for a decent price, however I was a little disappointed with the quality when I picked them up (in the picture it looked plastic but upon arrival it looks like molded Styrofoam - see attached image). Feeling bad for the lady I still bought them but now I am trying to figure out what the best way would be to make the texture of them look more like rock. My first thought is concrete but I feel like I will loose the nice rock shape the background already has so I wondered if there was something a little thinner I could apply and still achieve that rocky texture. As well, should I be sealing the back of the Styrofoam so it doesn't leach anything into the water? Thanks for the advice guys and have a good one!

[Regalblue]

I'd talk to Steve. Here's his DIY thread -> http://michigancichlid.com/simplemachinesforum/index.php?topic=5946.0

[Steve]

Styro won't leech anything bad as long as it's not some chemically treated stryo which most are not, especially since it's made for tank use. So I would not worry about that. Concrete will work but it does go on thick, is messy and does fill in details too much for my taste. I'd use Drylok like in the link Blair linked you to. That's the best way to add texture as well as keep details. Then you will have to seal it though with some pond armor sealer which is not cheap. Might be best to just leave it as is to be honest unless you don;t mind dropping the $79 on the sealer. or if you are local I think I may have some pond armor sealer left here, would have to look but pretty sure I do. So you could swing by here and I could seal it for ya free.