Water Heaters - pin holes in hot supply to house from gwh

I have a 40 gal Gas Water Heater. The output pipe (hot supply to house) has tiny pin holes leaking all over my basement. The pin holes are all over the hot output from the gas WH ( hot water supply to the house) This pipe is copper. The leaks are within 3 feet of the WH and leads to the water taps in the house from the WH tank). These pin holes are spraying a mist of hot water all over my basement since the pin holes are ONLY on the hot output copper pipe and not on the COLD inlet pipe to the water heater. These pin holes are many in number, and are randomly placed all around the copper 1/2 inch pipe leading from the tank to the house faucets. There is flecks of green splotches where the other pin holes have formed. However, all of them occur within the first 3 feet as measured from the tank. I turned off the water supply to the water heater, cut the pipe through the biggest pin-hole. Then used a large wrench to unscrew the copper nut of the hot water side (output from the gas WH) in the hopes that I could just replace the copper and solve the pinhole problem. When I unscrewed the hot pipe from the tank, a 3-foot long rod came out of the tank. this rod doesnt seem to be hollow but solid and easy to bend. this rod had a lot of white crusty stuff which i assume is hard-water deposits. this rod is attached to a plastic fitting stuffed up in the threaded connection which screws to the top of the gas WH output pipe. Attached to the plastic piece is the 3-foot long rod.

How does this plastic piece separate from the copper in order to replace the copper pipe above it?

What is causing the leaks? Once the copper is replaced, what do I do about preventing them from forming again?

One plumbing supply person thought the cause could be electrolysis. If it is caused by electrolysis, why is it only affecting the first 3 feet of the copper output side of the gas WH?

What color is the inside of the copper piping.....is it yellowish white?


There might be a grounding issue on the water heater OR the main line.


You could cut out that section of piping and have it sent off to have it tested at no cost to you to determine the cause.


There should be dielectric unions on your tank to separate from dissimilar materials when joining to the tank.


I believe you are describing an anode rod.......which sounds like it needs to be replaced.