bz and Bruce - I can not identify the species from the photo. Fine structures are used and need to be seen to taxonomically separate Gammarus fasciatus from Gammarus lacustris. Plus the seller my have "borrowed" the photo from some other source and it might not be the same species that he sells.

From my searches G.lacustris is a cool water (trout type waters) species and will not tolerate warm waters which could prevent it from reproducing. I think the species we want is G. fasciatus (14mm - 1/2"-9/16"); it does not get as big as G.lacustris (22mm - 7/8"), but it tolerates warmer waters and will more likely survive in our ponds.

bz needs to first do two things. 1. ask the seller for a species name and maximum size. Max size may tell us which specie it is.
2. Ask the seller what is the dominate rooted weeds species in the ponds where they get their scuds. Ask if they raise them or if they harvest from the wild. If they raise the scuds themselves then they will be able to provide helpful advice about providing the correct habitat so the scuds reproduce and thrive for us. I suspect they raise these in swampy, weedy - fine leafed, deeper wetlands without fish. Wood (Canada) sees lots of G.lacustris in combination with coontail.

Thanks bz for your help.

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