Geon, that is pretty interesting and worthy of trying but apparently not relating to the 101 G-Board and TPU of this particular forum string, as you stated "headaches using toroids"
If we were to try this with the toroid regardless just for a test.
For example a frequency maybe near 8.5khz x 6 = 51khz - 8.5khz = 42.5khz
This can be adjusted closer to certain frequency's in ranges.
I did not understand this until Steve wrote it out. Thanks Steve.
Its worthy of a try in an electrolysis system as you said, if it breaks the surface tension up then this is a good positive experiment many people should do on their various cells since it has a very good possibility of dislodging the sticky bubble layer.