Fake Rock Idea

[Patfish]

I put my plants into $1 oil pans and they are a good size and are stable so they dont get knocked over but they are not what I want to see in my pond when the water is clear.
My idea is from aquarium people on youtube. I'll take insulating foam sheets and stack and trim to form a rock shape with a hole for the plant to grow through. it will be a shell to go over the pot and look like a large rock.
The videos show people using cement or morter to cover the foam to look like stone. Some have aded color to the cement to look even better.
What do you think of the idea?
What kind of cement can I use? Fish safe?
I think even if left gray it would look like a rock.
I just want large lightweight rocks the exact size and shape that I want and have it cover my pots. (too much to ask?)

 

[addy1]

My lilies and other plants are in the oil pans. Once the muck, bit of algae, plants grow you don't even notice the pots.

 

[sissy]

Just like the liner a good pond hides the stuff you should not see or want to see .

 

[DoDad]

Here's a large one I made in 2004. It's winter now and the plants are dead.

 

[Patfish]

Here's a large one I made in 2004. It's winter now and the plants are dead.
View attachment 108259

how is it made?

 

[JamieB]

You’ll want to test if the foam / cement weight balance is enough to keep it from floating. But yes, I’ve seen the same things used for aquarium backgrounds. Very cool.

 

[Gordo33]

Search Don Perry on you tube . He has built ponds ,fax rocks and many other outdoor projects with cement. His videos offer great instruction. The cement work in his back yard is amazing . He converted a chain link fence into a fax rock fence all with cement.