Not sure yet what shrimp, mostly in the "gathering information" phase. I want to minimize mistakes if I do go forward with this idea. I have two albino corydora (that's all the tag said at LFS, but they're cute little guys) and three tiger barbs right now. May/may not keep the barbs depending on whether or not my old guy kicks the bucket. If I keep the barbs, no shrimp. I've made that mistake before.
Another question: this may sound dumb, but can you mix gravel and sand substrates? I have some really pretty gravel that my anubises have glommed on to, but I know the corys like sand better. Can I mix the two, or have gravel on the bottom and sand on top/sifted down into the gravel? Or can I just make a sandbox for the corys? Trying not to disturb my plants if I can avoid it. I don't know if there's some reason substrates shouldn't be mixed like that...and as I said, minimizing mistakes.