A well servicing fluid includes ingredients including a GLDA salt, a crosslinker, and a viscosifying agent that is not crosslinked by the crosslinker. A well treatment method includes forming a well servicing fluid with ingredients including a GLDA salt, a viscosifying agent, and a crosslinker, the GLDA salt containing a metal cation chelated with a GLDA anion. The well servicing fluid is inserted into a well in a formation. The method includes crosslinking the viscosifying agent and attaining a first viscosity of the well servicing fluid using the crosslinker. After the attaining of the first viscosity, viscosity of the well servicing fluid in the well is decreased to a second viscosity less than the first viscosity by using the GLDA anion. The GLDA salt may be a GLDA calcium salt and the crosslinker may be a zirconium crosslinker.