i use only water , white vinegar , and a little dawn dish washind detergent to break the water tension . this mixture works well enough for cleaning and wont Harm Plastic or Rubber. all the gunk in the carbs is turned into a alkiline material that ends up in suspension in the cleaning liquid . its a good idea to rinse with fresh clean water after the ultrasonic cleaning because the vinegar is acidic . no caustic chemicals , works great in heated ultrasonic cleaner. safe to use inside the house and it cleans quite well ................... and its cheap try it , you will be as suprised as i was good luck