It's one of the products used in the major leagues of tank and zoo set ups when scultping displays. The 307 Lite is fish safe, can be colored with concrete pigments, painted with water based paint, etc. The background is then painted with a clear epoxy coating. IMO a product like Polygem 307 Lite is the way to go when making a DIY 3D background. It could be placed over Drylok or directly on the foam. It bonds to almost everything except glass and plastic. Coloring the background is unlimited, and there is no leaching of harmful chemicals into the water.
If you decide to go this route, call Polygem....their tech support is wonderful. They have a bunch of products, but not all of them are fish safe, so it's imperative to order the right product. Online, you can only order small amounts of the stuff (they are working on their website, so that will change), but you can call them up and order the larger quantities. Other vendors may be selling Polygem in the future.
Polyurea is another product used in making rocky/tree backgrounds, where the the stuff is poured into preformed molds.
You ever have one of those days, then stumble onto a thread like this flip through the whole thing in a couple of hours and then feel like you can do anything... BECAUSE THAT JUST HAPPENED TO ME!
It's going to be exciting to see the amazing things people will come up with. Polygem should elevate DIY to another level. Just remember who first mentioned it on MFK.
Polyurea is the other product people should check out. I have not checked to see if it is available online. Universal Rocks is supplying me with thin sheets to build my backgrounds on. Since it is usually poured into molds, they poured it on pond liner for a thin flat sheet.
I have a new acrylic tank that I still need to decorate, but here's the link to it and the filtration set-up which is in the basement. The height of the tank is 30"; the walls are 1" except for the bow which is 3/4".
Here is my 360, 92x24x36 it is badly scratched,crazed and bowed but is working as a growout tank for now. with the filter and the 45gl tank tied on to it the whole system is 500 gl. It has been running for close to 1 year now.
Pacu Mom, Do you adopt ? I am thinking about going through my second childhood ; ]