We report on the optical power limiting properties of nano-sized carbon (single walled carbon nanotubes and carbon black) embedded in an aqueous-polymer matrix in the phase state of a hydro-gel. A polymer employed is Pluronic F-127, who simultaneously features as a stabilizer of the nano-carbon in a fluid water-polymer medium. Limiting thresholds of the composites are given in a bijection with a phase diagram (determined by DSC, rheometry and vibrational viscometry) of a matrix alongside its viscous characteristics and caloric properties of phase transitions involving the gel and micellar solution. Reversible gel-to-isotropic fluid transition of the matrix renders optical material thermo-healing with regard to optical breakdowns inflicted by high-intensity laser irradiation in the solid-like gel state.