Which Group 13 elements form stable hydrated 3+ ions in water?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — boron group element Modern version of the periodic table of the elements (printable).

The Group 13 elements that form stable hydrated 3+ ions in water are aluminum, gallium, indium, and thallium.1

In aqueous solution, these triply charged ions are held strongly by six water molecules. While boron is also a member of the boron group, it does not form a stable hydrated 3+ ion because the energy required to remove three electrons from a boron atom is too high, making the formation of a bare $B^{3 +}$ cation impossible.12