Two new nickel nitrates, diaquabis(3,4,7,8-tetramethyl-1,10-phenanthroline-kappa2N,N')nickel(II) dinitrate methanol solvate, [Ni(C(16)H(16)N(2))(2)(H(2)O)(2)](NO(3))(2) x CH(4)O, (I), and triaqua[2,4,6-tris(2-pyridyl)-1,3,5-triazine-kappa3N1,N2,N6]nickel(II) dinitrate trihydrate, [Ni(C(18)H(12)N(6))(H(2)O)(3)](NO(3))(2) x 3H(2)O, (II), are reported. In both structures, the cation is octahedrally coordinated, to two bidentate 3,4,7,8-tetramethyl-1,10-phenanthroline (tmp) and two water molecules in (I), and to one tridentate 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tpt) and three water molecules in (II). Both structures are stabilized by extensive hydrogen-bonding interactions.