| | Re: Treating shrimp disease with aquarium salt
In looking at your link for scutariella-japonica and this parasite's life cycle, I don't think that salt treatment will be very effective. Parasite eggs are shielded by the shrimp's exoskeleton, and won't get the full brunt of osmotic shock. And treating only the shrimp won't kill all the young parasites that have just hatched and are in the tank.
If the problem continues, I would look for a dewormer under farm supplies. Many farmers use levamisole as a dewormer for their livestock. Here, several hobbyists buy levamisole sold as a "goat dewormer."
Praziquantel is another dewormer, not quite as potent as levamisole, but better than salt. I had no trouble buying "Prazi-Pro" sold to aquarium hobbyists. Easy to use and did the job (killed guppy flukes).