Yesterdays battle with the hot water tank

Yep, had me a battle with the hot water tank and Ole Ben wants me to tell you all about it.  It sprung a leak in the flexible cold water inlet line.  I had my well water tested awhile back and it had a very low ph; it was very acidic.  That causes any metal to rust, or in the case of the copper flexible tube, eat a hole in it.  In the picture below you can see the cold water inlet plumbing.  I discovered that there is no shut off for it.  I am planning to put one where the yellow star is located.  I also noticed that the nipple on the right (red star) is badly rusted.

Here is another picture of the same plumbing as seen from above:

And here is a close up of the rusted nipple (red star):

Since there was no shut off, I had to shut the water off to the whole house. The shut off valve was the first priority. Went to the local hardware store and got everything I needed. Drained the tank (that took awhile) and then cut the inlet pipe and installed the shut off valve. Had a problem getting the male part of the compression fitting into the plastic pipe. Went back to the hardware store to see if they had a different size and they said to just heat the end of the plastic pipe. That I did with a hair dryer and it worked. So finally got the water back on to the house. Then I tried to get the rest of the stuff apart. The flex pipe was corroded so badly that it almost tore apart before it broke loose. The end of the existing nipple was rusted pretty bad so I tried to clean the threads as best I could and put it all together. Turned on the water, and you guessed it, it leaked at the rusted nipple.

Took it apart and tried to get the nipple out. My old pipe wrench would slip. The vice grips also slipped since I had to pull with all my strength. The nipple would not budge. So, back to the hardware store for a another flex tube, nipple, and a new pipe wrench.

I thought that I would never get that old nipple out. The rust had it dang near welded in place. Finally after repeated WD-40 soakings and a couple of pulled muscles, it came loose. I wanted to replace it with one an inch longer but the store was out of those and had to go two inches longer. To make a long story a little shorter, I got everything back together. SEE:

Here is the new nipple:

I thought that I was all done when I noticed a few drops coming from the area around the new valve.  It was the connection of the flex pipe to the plastic nipple.  It was not tight enough to compress the gasket.  I tried to tighten it and the nipple just kept going further and further into the valve.  I hate to have to drain the 40 gallon tank again just to redo the nipple.  I hate plastic plumbing.  Here is a picture of the culprit:

You all have a good day now, you hear?  It is the first day of summer.