Yes to the White Perch. Look up American Pondweed to see if that matches what you are seeing. As for the other plant, it's too fuzzy of a picture and too dried out to ID. Or it's starting to die - plants aren't typically that curly.

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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).