ben_manzella said:I would strongly encourage people to not use warm water from the tap or any other water that could potentially come out of the water heater. The inside of a water heater is disgusting with many disolved minerals. So run cold water only to fill up your tank. If you are concerned about the temp age it and heat it.
That is true, deposits do build up in water heaters, but they generally accumulate in the outgoing pipe from the water heater. If you blast the hot water on for a few seconds before you hook up the python, it blows out most of the concentrated deposits. I would imagine that older water heaters may also affect the quality of the outgoing water. The different water sources that we are all working with will also greatly affect the dissolved minerals that enter our tanks from the tap. However, my water quality is pretty good and, again, I haven't had any losses or signs of stress after water changes using the python. Good luck all and keep up on those water changes, no matter how you do them!