Solvent to dissolve transmission fluid?

[sequel95]

Hi everyone, I use a custom garden sprayer outfitted with a pressure gauge and brake reservoir top with clear tubes for my brake fluid and transmission fluid changes. When finished with a project, I clean the tank out with paint thinner, then warm water and pressurize it to remove all of the fluid.

My question is: I just replaced the differential fluids, transmission fluid and used my garden sprayer. I want to do brake fluid in a few weeks. Would you recommend a solvent that will dissolve the thick transmission fluid or should I use the paint thinner/water method, or would you not recommend using the same tank for brake fluid?

I appreciate your thoughts.

Tom