First of all, this is not an aquarium. This is a shaker charm.
I started by filling these molds with UV resin. I would have prefered epoxy resin but, I need quick result.
I took some rocks and plastic plants and started "gluing" them at the bottom to simulate the bottom of the tank.
I showed you how to make the gold fish. Here they are.
I want to have the "swimming effect" so I glued them with UV resin.
I cut a piece of shaker film. I was originally going to use the "cover" from the mold but it did not turn out the way I wanted to. So here I am improvising.
You'll have something that looks like this. This has nothing inside.
Puncture a hole to get the water in. When I did this, I added the water slowly in case there are leaks.
Here is the finished charm.