Natural Concurrent Infections with Black Spot Disease and Multiple Bacteriosis in Farmed Nile Tilapia in Central Kenya

Table 1

Mean values of physicochemical parameters of pond water.

Physicochemical parameters of water	Recorded pond value
(1) Temperature (^°C)	28.2^c
(2) Dissolved oxygen (mgl^−1)	4.2^c
(3) pH	8.5^c
(4) Total ammonia free nitrogen (mgl^−1)	15.8^a
(5) Alkalinity (mgl^−1)	112^a
(6) Hardness (mgl^−1)	68^c
(7) Nitrites (mgl^−1)	0.058^a
(8) Nitrates (mgl^−1)	58^a
(9) Phosphates (mgl^−1)	0.046^c

Note. The recommended range of physicochemical parameters of water for culturing Nile tilapia in ponds are temperature = 22–32^°C; dissolved oxygen = 5–7 mgl⁻¹; pH = 6.5–8.5; ammonia 0.3–2 mgl⁻¹; alkalinity 20–100 mgl⁻¹; hardness 10–100 mgl⁻¹; nitrite = <0.02 mgl⁻¹; nitrates = 0.1–4.5 mgl⁻¹, and phosphorous = 0.01–3 mgl⁻¹ [36–38]. Key: a = pond value was above the recommended range; b = pond value was below the recommended range; and c = pond value was within the recommended range.