Hence why i said... Quote "you should have THE cathode hidden in the side"
not "you should have A cathode hidden in the side"
I made an aluminium resivour with an acrylic window, similar to yours (cept yours isnt a resivour :P) andi hid the cathodes behind a wall, to reflect global light, and it illuminates the WHOLE inside, specially if you polish the inside of the container.
I reckon you should give it a go doesn't take much. or you could do it this way.
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