Our heater is about 6 months old. We knew the inlet pipe had a tiny leak
and have been watching it hoping impurities would fill it up. Instead a
soft crystalline growth is forming at several places on the heater and
downstream as well.

My husband, a competant handyman and mechanical engineer did the install
and We would like help figuring this out. Could the heater sacrificial
anode be malfunctioning? I believe all pipes in the house are copper or
iron.

We are also experiencing a pressure drop in the hot water lines only.