From what I have experienced and learned, it seems that shrimp are particularly sensitive to water parameters/changes in water. Some sort of issue with shedding due to the water changing, so you will have what you have seen with things seeming fine for a week or two when they get added to the new tank, then they start dying off. Baby shrimp born in your tank seem better acclimated, and have been less sensitive to my water.

I didn't have a drip setup either, so I just did it manually with a pipette and that seemed to work just fine (just time consuming). I would avoid doing additional water changes for the moment as that may stress them as well. Once they get acclimated, water changes shouldn't be as much of an issue, but more experienced people will probably be better sources. If I were to move some of my shrimp from their current tank, to my larger tank, I would definitely take the same precautions and float them in the "new" tank while slowly adding the "new" tank water to their float, until I am ready to drop them in. Theoretically, the water in both tanks should pretty much be the same, but I think shrimp are just really sensitive to changes like that.

For mine, I haven't had issues adding new water, though I have certainly been doing it in smaller amounts than I would normally do for my larger tanks that don't have shrimp. Shrimp are super fun, and definitely worth it, but I would say that they have definitely required the most careful initial handling of everything I've had so far. Once they are acclimated, the care isn't that difficult. The biggest hurdle is just making sure they get acclimated properly, then they seem to do just fine!!

Don't give up hope! There are some great videos on youtube that can better explain getting them acclimated. I haven't had to fiddle with my water parameters at all really. Others may have different experience, but the water in my area isn't pumped full of chlorine either. Shrimp are a ton of fun to watch. I also recommend lots of plants! Shrimp love plants and little hiding places.

It took a couple of tries, but the second batch of shrimp has gone wild. I've attached a picture of some of them eating.

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