They 'attack' the gills according to information of fish/koi keepers. But they antenna is the perfect part to spot parasites with microscope. Since they are transparent. Also in the legs I can find them. The parasite is very small, impossible to see with the naked eye.
Thank you for your tips. I will look into these products.
@bluestarfish Thank you. indeed they seem to be bullet proof, also creating spores that can even tolerate much more. You are right about the restock and sterillization. But I'm so hard trying to find a solution and still have a little hope left.
Also I believe this parasite could be the reason of a lot of other people having trouble with their shrimp. Since it's a very clear patterns of 1 or 2 shrimp that die a day, most of the time in the morning. Dead shrimp are eaten by others, spreading the parasite? They attack the gills, this makes it also plausible why most shrimp found dead in the morning when the oxygen level is at it lowest point. Also it seems to peak above 25c, which is the ideal temperature of this parasite. It's easy to find out if you have a microscope...