A　computer-controlled　digital　camera　was　used　to　examine　the　formation,　breakage,　and　regrowth　of　flocs　formed　by　kaolin　or　the　mixture　of　kaolin　and　humic　acid　with　aluminum　sulfate　(alum)　at　different　intensities　of　applied　shear,　as　well　as　for　continuous　optical　monitoring　(Photometric　Dispersion　Analyzer).　The　computer-controlled　digital　camera　could　record　the　flocs　size　and　morphology.　There　was　full　regrowth　of　flocs　in　kaolin　suspension　when　their　zeta　potential　was　close　to　zero,　regardless　of　intensity　of　the　applied　shear,　which　indicated　a　significant　reversibility　of　the　floc　break-up　process.　However,　such　a　process　displayed　a　distinct　irreversibility　at　higher　alum　dosage　when　the　flocs　were　positively　charged　as　the　intensity　of　applied　shear　increased,　though　there　was　full　reversibility　of　floc　breakage　at　low　applied　breakage　shear.　Addition　of　humic　acid　weakened　the　reversibility　of　broken　flocs　in　all　cases,　especially　at　high　breakage　shear.　Two-dimensional　fractal　dimension　(D(2))　of　regrown　flocs　in　kaolin　suspension　coagulated　under　condition　of　charge　neutralization　was　not　influenced　by　the　applied　shear　except　at　high　applied　shear　(400　rpm),　whereas　at　a　higher　alum　dosage　the　D(2)　decreased　as　the　applied　shear　increased.　The　D(2)　was　lower　in　the　presence　of　humic　acid.　Further,　the　D(2)　of　regrown　flocs　with　charge　neutralization　was　higher　than　that　with　higher　alum　dosage,　whether　the　model　water　contained　humic　acid　or　not.　Without　humic　acid　in　water,　the　residual　turbidity　and　particle　number　after　breakage　and　regrowth　were　both　decreased　as　the　applied　shear　increased　up　to　250　rpm.　Higher　breakage　shear,　such　as　400　rpm,　gives　higher　residual　turbidity　(or　residual　particle　number).　This　work　gives　new　information　and　a　better　understanding　of　the　regrowth　of　broken　flocs,　a　subject　which　is　of　considerable　practical　importance　in　water　and　wastewater　treatment.