Art project: bubbles

Hello,

I am  experimenting with bubbles to transfer onto paper to get interesting textures for my drawings and I was wondering if I could add anything to the mixture to diversify the textures I am getting. Maybe something that reacts with any of the components in the mixture but will still create bubbles when blown into a cup. Right now the mixes consists of diffent dilutions - with water (to get the desired tonality) - of indian ink, dishwashing liquid and sugar (to increase the strenght of the bubbles). To one tone I added salt which seemed to make the mixture more dense(?)(or it could be that the ratio of other components vs liquid was..unbalanced). Adding the salt seemed to produce more but smaller foam...

As an example: there are strands of the liquid soap (?) visible in the ink pattern that is attached. Maybe there is something I can add that will break up the tones/inkflow in a different way/even more?