cheesecake layer, moose layer, koi pond layer
glass koi fish in middle
white bean paste decorations. It was very hard for me to find the bean paste so I had to make my own. I used bamboo skewers for the lily flower buds.
I bought my gelatin supplies at Gelatinmarket.com I haven't found a US supply of gelatin that produces a clear gelatin that doesn't cloud or yellow like theirs does. Also, the supply is a good amount for future projects. Customer service is good and information and video instruction on YouTube is great.
I originally saw a video on YouTube entitled Koi Pond mousse cake by Grace Sun. I believe she's from South Korea. She has a very nice speaking voice, and the video is very pleasant to watch. I've watched it many times to figure out what to do.
I've had many problems with this idea. First of all, we do not have here what is available in South Korea, lol. Also, I live in a little po-dunk town about a mile as the crows fly from Mexico and even though I traveled to the closest bigger city, I still could not find white bean paste or those jelly cups she spoke about. That's why I went with real gelatin and tried to make my own white bean paste, which didn't work out to well. More on that latter. 
I was making this for a birthday party, so I had to make it bigger than what she had so I just doubled it. That worked out, but the layers were thin. I'll see if I can find my notes and if I can I'll write down what I did here for you. Otherwise, you'll have to figure it out from the video like I did.
There are a couple of videos on making white bean paste. Problem with that, it can go off color and turn pink. Another problem is you might not get it stiff enough. Third problem it takes a long time. The whole cake takes a long time, and this will add to it. If you decide to do this cake, it's a labor of love and an exercise in determination. I'm not sure I'd ever try it again. When I did it, my gelatin wasn't cool enough, my bean paste wasn't stiff enough and my Koi melted and so did my lilies. Alot of work, a lot of hours of work, undone. I decided to use lily buds instead of flowers because I was running out of time by that point. I ended up using a glass Koi that I had instead. You can barely see it in the picture.
A couple of days later I was looking around Ebay and found a Koi mold that I could have used for the gelatin and injected with color. It would have saved a lot of time if I'd seen that a couple months before when I was ordering supplies. Consider going that route and skip the bean paste all together. Of course, the bean paste does taste good and is cheaper. 
Will update this later as time allows
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