what is a replacement for realistic water? (diorama water)?

They make this stuff that hardens into fake water. Try going to like a model train or hoppy shop.

Diorama Water

I agree that Future** would work, and you can tint it with transparent food coloring or watercolor, e.g. or with translucent acrylic paints, etc.

Or you can just paint the surface of the depression where you'll be adding the faux water, then just pour the clear Future/etc in plain.

There are other ways and materials/techniques for making faux water, but some of them depend on the look and depth of the water you want... a still pond, a brook, a small river (maybe even whitewater river), a big river, an ocean, a waterfall, etc?

And those materials and techniques can also create more realistic water or just reasonable "water" as well.

Check out some of the info on making faux water on this page of my site:

http://glassattic.com/polymer/other_materials.htm

The main ways use 2-part resins (usually epoxy resins, and sometimes polyester resins) or even acrylic medium (from the art or craft store), but also check out the section called "Simulations of Resin" on that page).

** now called Pledge with Future Shine in the U.S., but any cyanoacrylate floor polish will work (Mop 'N Glo, Klear, etc) ... a clear polyurethane would be simpler but thicker to pour

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when I was in high school I painted a picture of a log cabin, set in the woods a little ways up from a river. what i did to make the water look more real was to add a few "white caps" and varitations of blue to give it an appearence of movement. you could show the water rippling away from the duck to show movement, hope that helps

A cheap way is to use Future floor polish which is 100% clear acrylic. I would put it down in layers so it dries OK. Here's a good site on how to use it, etc.:

http://www.swannysmodels.com/TheCompleteFuture.htm...