I live on a private well and have had a tank for a while. Every few months I'd have to chlorinate the tank (with hydrogen peroxide) to get rid of the rotten egg smell.

Two local plumbing companies advised that the smell was caused by sulfate-reducing bacteria, confirmed by numerous online sources.

I could get rid of it by draining a gallon out of the tank, opening the temp & pressure relief valve, pouring hydrogen peroxide into the tank, and letting this solution flush through the pipes and sit for a few hours.

About a month ago I noticed the smell again and was planning to chlorinate the system. Unfortunately shortly after, the tank was leaking, so I replaced it and "upgraded" to a tankless system.

Now the problem is, after a month, the water still smells. Obviously there is no more anode rod or sitting water, so there must be bacteria still in my pipes. It's mainly coming from one faucet in the kitchen.

How can I flush that pipe, or kill the bacteria in some other way?

Odor in the cold water that goes away after water flows... the most likely source of the hydrogen sulfide is Sulfate-Reducing Bacteria 1

I live on a private well and have had a tank for a while. Every few months I'd have to chlorinate the tank (with hydrogen peroxide) to get rid of the rotten egg smell.

Two local plumbing companies advised that the smell was caused by sulfate-reducing bacteria, confirmed by numerous online sources.

I could get rid of it by draining a gallon out of the tank, opening the temp & pressure relief valve, pouring hydrogen peroxide into the tank, and letting this solution flush through the pipes and sit for a few hours.

About a month ago I noticed the smell again and was planning to chlorinate the system. Unfortunately shortly after, the tank was leaking, so I replaced it and "upgraded" to a tankless system.

Now the problem is, after a month, the water still smells. Obviously there is no more anode rod or sitting water, so there must be bacteria still in my pipes. It's mainly coming from one faucet in the kitchen.

How can I flush that pipe, or kill the bacteria in some other way?

Odor in the cold water that goes away after water flows... the most likely source of the hydrogen sulfide is Sulfate-Reducing Bacteria 1

I live on a private well and have had a tank for a while. Every few months I'd have to chlorinate the tank (with hydrogen peroxide) to get rid of the rotten egg smell.

As far as I know, this smell is caused by a combination of: anode rod, hot sitting water, and bacteria. I could get rid of it by draining a gallon out of the tank, opening the temp & pressure relief valve, pouring hydrogen peroxide into the tank, and letting this solution flush through the pipes and sit for a few hours.

About a month ago I noticed the smell again and was planning to chlorinate the system. Unfortunately shortly after, the tank was leaking, so I replaced it and "upgraded" to a tankless system.

Now the problem is, after a month, the water still smells. Obviously there is no more anode rod or sitting water, so there must be bacteria still in my pipes. It's mainly coming from one faucet in the kitchen.

How can I flush that pipe, or kill the bacteria in some other way?

I live on a private well and have had a tank for a while. Every few months I'd have to chlorinate the tank (with hydrogen peroxide) to get rid of the rotten egg smell.

Two local plumbing companies advised that the smell was caused by sulfate-reducing bacteria, confirmed by numerous online sources. 

I could get rid of it by draining a gallon out of the tank, opening the temp & pressure relief valve, pouring hydrogen peroxide into the tank, and letting this solution flush through the pipes and sit for a few hours.

About a month ago I noticed the smell again and was planning to chlorinate the system. Unfortunately shortly after, the tank was leaking, so I replaced it and "upgraded" to a tankless system.

Now the problem is, after a month, the water still smells. Obviously there is no more anode rod or sitting water, so there must be bacteria still in my pipes. It's mainly coming from one faucet in the kitchen.

How can I flush that pipe, or kill the bacteria in some other way?

Odor in the cold water that goes away after water flows... the most likely source of the hydrogen sulfide is Sulfate-Reducing Bacteria 1