I did it! Mirrored Coral Reef Wall versions! (Patreon)

In the images above I used them to make some sort of see-through into to aquarium by placing a normal and mirrored version on each side of the window. As both objects are walk-through-able, I've also added an extra fence in front of the coral reef on the outside, so Sims won't walk straight through it.

What can't be seen, is that when looking in an angle from one side to the other, you will see some holes in the middle where the two objects meet. This is because the bottom, or in this case the back of the coral reef is transparent-ish for a large part. You can sort of fix this by placing other plants, rocks or the normal ground coral reef underneath it. I will upload another example of these wall coral reefs mixed with the normal coral reef later today. I will then place them in the ocean instead of in the pool.

There're some other rocks too without coral which I might add to this "pack" too. I first need to see what can be done with those. Probably only some shrinking and recolors.
Other coral objects will be part of a next pack which I will probably work on after this one is finished. :)