make more foam when you brush

I always buy a specific brand toothpaste (turns out it is SLS free) but broke from my routine and bought crest or colgate or something. I use a small amount but I have to empty my mouth of foam midway through brushing. I hate it. Gross.

I also have a canker sore but have been brushing my teeth more often thinking it would help. I guess not.

I have another toothpaste (clinipro) which is not foamy enough, I always feel like I’m running out of toothpaste as I’m brushing.