I have an old (20yr?) Culligan mark59 with a small leak in the thin black tube that goes from the regeneration unit to the salt tank. The tube seems to be compressed at one point under the metal frame where the plumbing pipes enter the unit, and I think the tube is just slightly cracked under that "pinch point". I see a small puddle of water on the top of the unit under this tube, that then drips onto the floor under the unit.
How do I remove the metal frame on top of the unit to replace this thin tube? Any pointers appreciated.