I have a Maytag refrigerator. We've been having trouble with stuff coming out in our drinking water. We've tried to flush the system to no avail. This doesn't happen with any other water in the house. We've also changed the filter.

I'm looking to replace the Water Tank. I wanted to see how hard it would be before I ordered the part so I took the back off the unit and I can see where the water reservoir goes up into the refrigerator compartment and then comes back down. However, when I follow the line that goes to the front door water spout, it then goes into some metal (see attached photos). Then at the front of the fridge, it comes down from the frame. I'm not sure how to get his out to install a new one.

I'm attaching some photos for your reference.

Also, what is the grey colored goop that is around the water line? It feels more moist than caulk?

Maytag Refrigerator (Has a whirlpool sticker inside)
Model: MSD2651KES

Model Link: Parts for Maytag MSD2651KES Refrigerator - AppliancePartsPros.com