Ferric iron is relatively insoluble in water. A salt (chemistry) of ferric iron hydrolyzes water and produces iron(III) oxide-hydroxides while contributing hydrogen ions to the solution, lowering the pH compared to a solution of equal molarity (based on the anion concentration) solution of the analogous sodium or potassium salt.
Ferric dosing can be used to mitigate the impact of nutrient loading in lakes by reducing the bioavailability of phosphorus in the water column. This can aid management strategies for reducing eutrophication in lake systems.
A synonym of ferric, deriving from the Germanic roots instead of the Latin, is ironic. For example: magnets only attract to ironic substances.