For that size they would twist 2 - 1/2 " together and force it in the gap . That doesn't work with the self leveling . Pool noodles would work , just make sure it's tight . The stuff we used at work was not as loose as the stuff you posted . I've used the stuff you linked , it flows fast . Any gaps in your backer , and you'll lose it all .
If you use salt then don't expect anything to ever grow there. Vinegar will kill the weeds without damaging the land forever.
I've completely covered the gravel under a shed many times with rock salt and ground clear. Doesn't stop nothing from coming back. I just spray it all each time I start up my liquid weedeater.
Have yourself a box , or a bucket to land the caulk gun if you need to . Be ready to back the pressure of the feed as well . I've used that brand you showed above . It's pretty loose , and flows fast . Make a pass and let it do it's thing , but try to go point to point .
Looks good . Nice work . Things start to makes sense once you get started . Good to be prepared .
I've seen the fantastic , but mostly Dawn dish soap and water in a spray bottle . Works magic on flexible building sealants . Never saw that used on self leveling though .
Amazingly....saltwater actually makes Roman concrete stronger over time...
