Who Does That?

I was needing to drain my pool. The water in the pool needed to be stabilized. I contacted the pool company that normally does the maintenance for me. After about one and a half weeks of communicating, I had no success. I called The Pool Boys and they said a Technician would contact me. Thirty minutes later, Justin called me and asked me to text him pictures of my system. After receiving the photos, he called me right back. Over the phone, he gave me instructions on how to drain my pool. It worked. I called Justin back and told him about my success. I asked him how much I owed his company and he said no charge. Then I told him that I wanted to at least give him a tip, he said there was no need for that. Who does that?