Sorry not much help here, I have a pond, but don't recognise the plants. Are they purchased from a store or wild? The first one kind of looks like cardinal lobelia, but very small. The "watercress" plant reminds me of something from an aquarium store. The last pix looks vaguely like primrose. But no bells going off here for sure. Good Luck
Imp- maybe try the easy garden site. There's an id this plant forum.