UPD2: Tons of thanks to all of you again! I didn't even hope for such a positive response!
UPD: Thank all of so very much! I'm sorry, I don't reply to everyone personally, but I just don't know enough English words to express my gratitude. MLP-fandom is the most crafter-friendly fandom ever!
It's finished! v^_________________________^v
It was my first serious job on imitating water, so I couldn't realize everything I wanted, but I'm still very happy. When I first got this idea several months ago, I was like "come on, you'd never be able to do smth like that!" and now here it is standing in front of me.
Water made of the epoxy adhesive, pony made of polymer clay, rocks made of rocks xD