Bubble Bomb Recipe

I am looking for a good bubble bomb recipe. I recently started using SLSA in my bath bombs, but I am having issues with them cracking slightly at the seam. I have tried adding more/different oils and butters to hold them together, but after about 24 hours, they almost all crack slightly. I never had this problem before I started using the SLSA. Is there a different ingredient I should be using to get bubbles from my bath bombs? Any good recipes are much appreciated! TIA!