In the experiments varying calcium concentration, C Ca 2+ ranges from 10 to 200 mM at fixed total flow rate Q T = 1.2 µL/min and C Alg = 0.1 mg/mL. In the experiments varying the gel concentration, C Gel , Q T is fixed at Q T = 6 µL/min. In these, C Alg ranges from 0.02 mg/ml to 0.2 mg/ml, keeping the calcium crosslinking ratio fixed at C Ca 2+ =1000 mM per C Alg =1mg/ml. In varying Q T , the same crosslinking ratio is used, with C Alg = 0.1 mg/ml and C Ca 2+ = 100 mM, while Q T ranges from 1.2 to 12 µL/min. For all conditions in Table , the concentration of sodium is proportional to the concentration of alginate or calcium, respectively. We find that sodium chloride is a necessary component in the gel deposition and ablation process, as described in SI Fig. . Table also indicates the total number of deposition/ablation events recorded and the total duration of each flow test. The exploration of the flow phase diagram, in Fig. , represents many more experiments within the limits of alginate concentration between C Alg = 0.02 mg/mL and 10 mg/mL and calcium concentration between C Ca 2+ = 0.5 and 1000 mM, all obtained at Q T = 1.2µL/min.