Table 4 The average results of determining the color changes of indicator biofilms at different pH.

pH₁

0.00 ± 0.00 ^d

43.98 ± 0.96 ^c

44.15 ± 0.97 ^bc

45.38 ± 0.53 ^ab

46.22 ± 0.53 ^a

pH₂

0.00 ± 0.00 ^d

48.75 ± 0.58 ^c

49.03 ± 0.58 ^bc

49.50 ± 0.26 ^b

50.56 ± 0.15 ^a

pH₃

0.00 ± 0.00 ^d

36.55 ± 0.22 ^c

37.70 ± 0.20 ^c

41.19 ± 0.92 ^b

46.14 ± 0.71 ^a

pH₄

0.00 ± 0.00 ^e

40.07 ± 0.51 ^d

41.29 ± 0.49 ^c

44.56 ± 0.65 ^b

49.63 ± 0.85 ^a

pH₅

0.00 ± 0.00 ^d

42.29 ± 0.53 ^c

42.95 ± 0.51 ^c

47.84 ± 0.64 ^b

50.46 ± 0.23 ^a

pH₆

0.00 ± 0.00 ^e

45.94 ± 0.05 ^d

47.24 ± 0.48 ^c

51.11 ± 0.49 ^b

53.04 ± 0.00 ^a

pH₇

0.00 ± 0.00 ^c

49.47 ± 0.91 ^b

50.83 ± 0.91 ^b

53.32 ± 0.75 ^a

54.47 ± 0.47^a

pH₈

0.00 ± 0.00 ^e

45.42 ± 0.22 ^d

47.11 ± 0.24 ^c

49.89 ± 0.92 ^b

51.58 ± 0.10 ^a

pH₉

0.00 ± 0.00 ^c

45.19 ± 0.67 ^b

46.33 ± 0.67 ^b

51.58 ± 0.68 ^a

52.36 ± 0.87 ^a

pH₁₀

0.00 ± 0.00 ^d

52.04 ± 0.57 ^c

55.84 ± 0.83 ^b

56.57 ± 0.81 ^b

58.06 ± 0.82 ^a

pH₁₁

0.00 ± 0.00 ^e

50.96 ± 0.28 ^d

57.13 ± 0.68 ^c

60.74 ± 0.76 ^b

62.66 ± 0.76 ^a

pH₁₂

0.00 ± 0.00 ^e

35.48 ± 0.31 ^d

41.10 ± 0.32 ^c

46.02 ± 0.18 ^b

47.85 ± 0.16 ^a

pH₁₃

0.00 ± 0.00 ^d

26.07 ± 0.03 ^c

26.81 ± 0.29 ^c

32.98 ± 0.90 ^b

34.81 ± 0.88 ^a