My parents emigrated to the US from Aschaffenburg in 1957. My grandmother's maiden name was Katharina Glaab (1904-1962). Her father was Konrad Glaab (1878-1965), a Main River fisherman. Konrad was married to Elisabeth Dauster (1882-1961) and, in addition to my grandmother, there were Franziska, Elisabeth, Andreas & Peter (twins) and Annemarie. Konrad's father was Nikolaus Glaab (1851-1930), who was married to Franziska Weitz (1853-1930). Nikolaus Glaab was also a commercial fisherman.
I remember as a child, going to the Aschaffenburg Fish Market,a weekly open-air market, where all the fishermen displayed their catches in big galvanized tubs. When a fish was sold, it was gutted and great-grandfather would throw me the bladder, which I popped by jumping on it.
If there are any in the community who belong to this line, I'd love to hear from you. Glaab is not a common name in Germany and most of the Glaab's (371 surname bearers according to one source) are concentrated in the Aschaffenburg-Kahlgrund area (that is, along the river between Aschaffenburg and Frankfurt, the next major city.)