I"ve used a ton of that stuff. WEAR GLOVES, it's impossible to get off your hands. It can be useful but it's a mess. Also I really didn't think the look of it was an improvement over the black plastic. The only thing that works for me to cover up black plastic is real rocks.

The search feature is not working properly but there should be lot of discussions in the archived posts. This subject comes up frequently and some of the discussions have been very interesting. If you want additives like pebbles it would be best to lay them out and add the Great Stuff on top of it. GS forms a skin as it cures and might resist the additives.
As GF ages it is an ugly orange brown. It sticks to liners but can usually be pulled away if the liner is flexible but a rigid surface always has remains. Sandy

Hi
Have used the "stuff in almost every conceivable manner.lol The most ambitious is a 7x10 foot waterfall.
The oldest is a 180 rift lake cichlid tank ,used as a cave sytem setup in 01.
It has a lot of advantages but also some drawbacks lol.
Requires a coat of paint as it is a sickly color and will degrade in UV light. It will not hold water so can't be used as a dam.
There are 3 different degrees of expansion. I find the least expanding the strongest.
For islands i place some plastic pots in a group spray the foam around them leave space between so foam gets all around each pot. Do this on a smooth flat surface after curing it will pop off by running a blade under it. Not too wide as it tends to curve while curing.Requires a coat of paint,not only to improve the color but to protect from UV. I use acrylic latex but two part epoxy is more chip resistant also about 3 times more expensive lol.. Underwater use is limited as it's so bouyant it will pop off of a smooth surace.. This can be overcome by curing painting and gluing to surfaces using silicone .
How artistic are you?? Given the range of color in acrylics you can make many faux finishes . I've done marble lapis and even tiger eye and opal. Might mention that plants will root right through it spoiling the effect lol On the waterfall I find the "bleeding" effect rather interesting. You can also get it in a black color at about 4 times the price. It will fade overtime anyway.
BTW I find that if you want to add other materials such as rock limbs bark sand coatings . It's best to cure it paint then silicone the additive. Greatly expands the adhesion time. Makes a wonderful base for moss gardens by doing the above but adding coir with the silicone.
Good luck with whatever you decide . To me the pros outweigh the cons. gary

I guess a lot of it depends on your personality. In order to keep the peace, I don't allow DH to use the stuff. He has a low frustration level with anything that is considered a construction material.
It is always a mess to use and it must have air to expand in. I tried to seal some in a plastic bag once when I was trying to make fake rocks and it just turned into the resin that is in the can. Very disappointing. Sandy

Sandy
I alwys felt that that's the purpose of gardening particular with ponds . If you aren't frustrated you're not doing it right lol?? There are other choices for making fake rocks such as tufa, and some resinous acrylics.. I have nevr used them but have seen some fantastic terrariums as well as reef aquariums using the material. The advantage over stuff is it holds color looks more natural and much more resistant to wear. The cost is about 4/5 times that of stuff and is very heavy.
I'm trying to make some "limbs " out of the stuff to hold epiphytes without looking like pots. I have absolutely no artistic talent my rocks usually look pretty fake .yet to find out about the limbs lol gary