TABLE 1.

Nutrient amendments performed using water from the epilimnion in Flathead Lake^a

Start date	Unamended control	N + C	P + N	P + N + C	2P + N + C	MPn + N	MPn + N + C	2MPn + N + C	MPn + P + N + C	Conditions
2 August 2017	+	−	−	2:30:106	−	−	02:30:106	−	−	Dark, 22.5°C
2 July 2018	+	16:106	−	1:16:106	−	−	1:16:106	−	−	Dark, 22.5°C
24 July 2018	+	16:106	−	1:16:106	−	−	1:16:106	−	−	Dark and light, 22.5°C
9 August 2018	+	−	−	1:16:106	−	−	1:16:106	−	0.5:0.5:16:106	Dark, 22.5°C
20 July 2020	+	−	1:16	1:16:250	2:16:250	1:16	1:16:250	2:16:250	1:1:16:250	In situ light and temperature
7 July 2021	+	16:250	−	1:16:250	−	−	1:16:250	−	0.5:0.5:16:250	In situ light and temperature

^a All ratios indicate micromolar nutrient additions. Symbol + or a ratio indicates the amendment was performed, while symbol − means it was not performed. P, phosphate; N, nitrate; C, glucose; MPn, methylphosphonate.