How to stop rocks from sliding into steep sided small pond

[GBBUDD]

I used waterfall foam to fix some of the side wall and top stones in our pond from being dislodged by the neighbour’s dog every time he came for a drink. It is fabulous stuff.

Time will tell how it holds up

 

[pebbleoz]

Time will tell how it holds up

I guess so. The dog visits daily and i did it 12 months ago. All the black foam is hidden by rocks and so no UV light gets to it.
Most of the rocks are selF supporting, large ones at the bottom on a shelf then smaller ones above them. A few small ones are just held there by the foam as they were pushed in to cover the foam - it’s tricky stuff to use as it expands.

 

[GBBUDD]

I guess so. The dog visits daily and i did it 12 months ago. All the black foam is hidden by rocks and so no UV light gets to it.
Most of the rocks are selF supporting, large ones at the bottom on a shelf then smaller ones above them. A few small ones are just held there by the foam as they were pushed in to cover the foam - it’s tricky stuff to use as it expands.

I did very similar in what I call the dead pool of my pond its a 30 inch shallow area where the rocks are leaning against a angled wall where like your self the foam is behind the rocks locking them in uv should not be an issue time will tell

 

[Lisak1]

Yup - for small jobs waterfall foam is great. It does degrade over time, but if you aren't relying on it to provide structural support it's no big deal. We foamed some rocks into the spillway rock on our pondless waterfall - they're still in place, 9 years later. But I know if I wanted to, I could dislodge them with a good tug and a little prying.