from what I have heard it is sort of like breeding guppies lol.
IMO I would say you could fit about 10 shrimp in there, depending on what kind you get. I would, myself, do something like 15 ghost shrimp, or ten amanos or red cherries, or 7-8 flower shrimp, and any combo of that. I do not have much experience with shrimp, just the three amanos I have, but As I guess that is what I'd probably do.
But to know for sure, just start slow, same as with fish. Add a few and watch water p-rams. If they stay at a low trate level for a long time then try adding more, and so on and so forth
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