How do I glue the stones of my pond waterfall?

In this article, I have decided to introduce you to TOUCH'N FOAM. It is something I use to easily glue stones in a pond waterfall. This foam allows you to easily secure stones in a waterfall. You can glue the stones together. You can also glue them onto the liner. Be careful: remember to wear gloves so you don't end up with black hands for several days.

This foam for waterfalls allows you to adhere stones to cement, wood, and fabric. It is ideal for replacing mortar and gluing stones in a waterfall. This foam can also be used to direct the flow of water in a waterfall or drop, and it is safe for your fish.

• Bonds to rock, stone, wood, and most pond materials
• Does not fade like standard foam - no painting required
• Expands to fill gaps and voids
• Easier and cheaper than mortar (cement).
• Adheres to rock, stone, wood, and most materials.
• Seals holes in trees to repel pests
• Can be used as craft foam for artificial plants

This waterfall foam or adhesive foam is great if you want to achieve a beautiful waterfall or stream. Black in color, it takes on a lighter color comparable to that of an EPDM liner. You can use this foam to glue stones onto an EPDM or PVC liner.

Foam, glue, or mortar: what should you choose for your waterfall?

The three solutions do not perform the same job. Expanding foam fills voids and forces water to pass over the stones. Instant glue secures a small piece of decor. Mortar, on the other hand, is reserved for masonry structures and very large load-bearing stones.

Fresh mortar releases lime that can raise the water's pH: if you use it, let it harden thoroughly and rinse the structure before circulating the pond water. On a flexible liner, it also tends to crack when the ground shifts, which foam handles better.

Gluing waterfall stones step by step

A successful waterfall is prepared dry. Take the time to place your stones before taking out the foam: once expanded, it cannot be repositioned.

1. Protect the liner. Slide a piece of geotextile felt under heavy or angular stones to prevent them from piercing the liner.
2. Dry-fit the waterfall. Place the stones without glue, run the water for a few minutes, and adjust until you get the desired water curtain.
3. Clean and prepare. Remove dirt and dust from surfaces to be glued, put on gloves, and read the foam instructions.
4. Inject the foam behind and under the stones. Fill the voids in small amounts: the foam expands, so it is better to add more later than to have it overflow.
5. Let it harden. Do not move the stones anymore and only restart the water flow after the drying time indicated in the instructions.
6. Finish with a utility knife. Cut the excess visible foam and camouflage the joints with gravel or sand pressed onto the still-fresh foam.

Directing water and avoiding leaks

Foam isn't just for gluing: it blocks passages under and behind the stones, where water likes to infiltrate. A waterfall that "loses" water is often one where the stream goes under a stone and comes out outside the liner.

• Keep the edges of the liner raised above the water level all along the stream and waterfall.
• Overlap the liners in the direction of the flow: the top liner should go over the bottom one. Our article on overlapping two EPDM liners in a stream details the process.
• Fill the underside of each weir stone with foam so water does not slip underneath.
• Check after a few days that the pond level remains stable with the pump running.

Don't want to place stones one by one? Preformed pond waterfalls are installed faster. For flow rate, choose a pump from our range of pond pumps for filters and streams.

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