The Chalk River Unidentified Deposits (CRUD) behavior of corrosion products on cladding materials is a critical factor influencing the longevity and safety of nuclear reactors. Fe and Ni are considered primary sources of corrosion products. However, trace impurity ions such as Mg, Al, Si, Ca, and Cu can also be introduced into the reactor core through material corrosion processes. This study investigates the influence of these impurity ions on the deposition behavior of CRUD on Cr-coated and uncoated Zr alloy cladding tubes, employing large-scale internally heated loop systems and material analysis techniques. The results reveal that Mg, Si, and Al exhibit strong tendencies for CRUD deposition, whereas Cu shows limited deposition behavior, and Ca is largely uninvolved in CRUD formation. Mg and Si are predominantly deposited in the outer layers of CRUD. Notably, an Al concentration of approximately 7 ppb in the coolant alters CRUD composition, while a Cu concentration of around 5 ppb has negligible effects. Despite coolant Ca concentrations exceeding 150 ppb, Ca is almost entirely absent from CRUD. Under a 300 ppb DO environment, Cr-coated tubes experience accelerated CRUD deposition due to Cr(VI) species generated through surface dissolution reactions. This leads to the formation of a Cr-rich inner layer in the CRUD. In contrast, this effect is minimal for uncoated Zr alloy tubes.