Hydrogels are viscoelastic fluids comprising interlinked organic molecules and are valued for their softness, flexibility and biocompatibility. We report on a small peptide, EL-5F, that rapidly and reversibly self-assembles into beta-sheet amyloid fibrils at low pH, corresponding to protonation of its acidic residues – resulting in a weak hydrogel. Furthermore, this gelation behaviour is enhanced by PEGylation of the peptide at the N-terminus as a result of increased peptide solubility. Before these intriguing hydrogels can be practically implemented, a comprehensive characterization of their response to a variety of stimulii is required. We present a systematic study of the influence of several variables, namely: pH, concentration, ionic strength and PEG length on the structure of these peptide hydrogels at the molecular and macroscopic level.