Tris(5-amino-1H-1,2,4-triazol-4-ium) dihydrogenphosphate hydrogen-phosphate trihydrate.

In the crystal structure of the title molecular salt, 3C2H5N4(+)·HPO4(2-)·H2PO4(-)·3H2O, the phosphate-based framework is built upon layers parallel to (010) made up from the H2PO4(-) and HPO4(2-) anions and water mol-ecules, which are inter-connected through O-H⋯O hydrogen bonds. The organic cations are located between the phosphate-water layers and are connected to them via N-H⋯O hydrogen bonds. The bond-length features are consistent with an imino resonance form for the exocyclic amino group, as is commonly found for a C-N single bond involving sp(2)-hybridized C and N atoms.