We used a resin with catalyst on most of it. It's pretty difficult to work with and requires accurate measurements and more accurate timing. There are other downsides too, like it eating away at the foam, the bubbling we saw (which worked out), and the surface being sticky for 2 weeks while it "dried". Most of that can be avoided by mixing the resin with the catalyst quickly and appropriately and then getting it laid down but it's a lot harder than it seems.
We also used the GW water effects. It worked out remarkably well but is a bit on the pricey side.
We didn't experiment with coloring the resin / water effects at all. On the swamp table it ended up looking a bit more blue in parts because it began to eat at the foam... which gave it color. Heh.