I hope you have that MDOC person's name. I'd call them, ask for his supervisor and explain how the visit went. Ask if another person is available to come out for a consult, and get their name before they come out.

From the pics, they look like mosquito fish to me.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).