I finally found shrimp fry in my tank, and while hunting for more I spotted a hydra on a plant. Once I found one and removed it I noticed they are all over my tank. I read these are very harmful to shrimp fry, how do I rid myself of these?
Hydra suck. This small creature eats your fish. You want it removed from your aquarium and QUICK! I'll show you how to quickly identify and kill hydra.
I would not use any chemical treatment in a tank with shrimps as the chemical will probably kill the shrimps as well. That leaves just removing all the ones you find, which will be very hard to do as they hide so well, and fish to eat them - but the three mentioned in the article will probably also eat shrimps.
Can you remove your shrimp and then treat the tank with flubendazole? That got rid of my hydra - but I don't know how lethal any leftover traces would be to shrimp. Possibly very.