I had some once but spotted them fairly early I think. They got into the tank from stuff I took from an outside pond and put into the tank. I took everything out except the substrate, then fished out the scuds, checking frequently for a few days. After a couple of days I started returning the very carefully checked over contents and shrimp. It worked out well but did mean a lot of work! The tank had been running for a few years and so was due to be redone anyway so it wasn't too big of a deal for me, but there was still the possibility I didn't get them all and they would then return, though I must have got them all as that didn't happen, thankfully. I re-used everything from the tank, just used a bucket to check each item over very carefully before returning it to the tank.
The scuds aren't harmful, and even indicate the water is good if they are doing well. Any treatment you could try is almost certainly going to also kill shrimp! You can just keep fishing them out when you see them, but that will likely become a never ending chore, but can keep the numbers low if you don't mind seeing them occasionally, some people actually quite like the extrra diversity.
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sdlTBfanUK ·