Most plants you get from a store will have pesticides. Anyways quarantine your plants in a tank without invertebrates. You’ll want to run carbon in your filter for at least a week, but it may take a month to fully remove all pesticide traces.
Update: unfortunately I ended up losing all of them in the quarantine bucket. I checked on them and they were swimming and behaving rather normally and when I returned an hour later all but 1 were dead. It passed as well shortly after. 🙁
I am sorry you lost them – This happened to me too. After purchasing a surprise pack (from a reputable place that I buy from all the time) I saw the original listing (Elodea) stating about this particular plant being imported/sprayed and warning ‘unsafe for invertebrates’ pesticides may be used. They suggested that rinsing in warm water would get rid of the poison.
I rinse the plant and left them in a bucket for a week and changed the water twice. When I planted them in – the next morning (12 hours later) my whole colony was dead. All the babies had turned inside out – some of the adults (neo and Amano) were twitching still so I saved all I could.
The biggest amano was resurrected within an hour and the other two later that day. The neos stayed dead/died that day except four big ones.
I did a massive water change and threw all the Elodea away.
Don’t believe the rinsing will do anything. I wish I had just thrown the whole thing in the bin at the start.
That’s so weird.
I’ve never had an issue with any plants having pesticides on them.
But the store I work at also gets plants from a place that grows them immersed already.
I’m so sorry this happened to you. I’m glad it seems you’ve saved your shrimp!
CanadianGoof 
Most plants you get from a store will have pesticides. Anyways quarantine your plants in a tank without invertebrates. You’ll want to run carbon in your filter for at least a week, but it may take a month to fully remove all pesticide traces.
Run a hob filter with activated carbon in it for a bit. This helps pull any of the chemicals from your water column.
Update: unfortunately I ended up losing all of them in the quarantine bucket. I checked on them and they were swimming and behaving rather normally and when I returned an hour later all but 1 were dead. It passed as well shortly after. 🙁
I am sorry you lost them – This happened to me too. After purchasing a surprise pack (from a reputable place that I buy from all the time) I saw the original listing (Elodea) stating about this particular plant being imported/sprayed and warning ‘unsafe for invertebrates’ pesticides may be used. They suggested that rinsing in warm water would get rid of the poison.
I rinse the plant and left them in a bucket for a week and changed the water twice. When I planted them in – the next morning (12 hours later) my whole colony was dead. All the babies had turned inside out – some of the adults (neo and Amano) were twitching still so I saved all I could.
The biggest amano was resurrected within an hour and the other two later that day. The neos stayed dead/died that day except four big ones.
I did a massive water change and threw all the Elodea away.
Don’t believe the rinsing will do anything. I wish I had just thrown the whole thing in the bin at the start.
That’s so weird.
I’ve never had an issue with any plants having pesticides on them.
But the store I work at also gets plants from a place that grows them immersed already.
I’m so sorry this happened to you. I’m glad it seems you’ve saved your shrimp!