I follow two methods of pretreating shrimp before using in recipes. One is outlined in Serious Eats recently but that's been a standard for a long time in many Chinese style cooking. This one uses 1 tsp salt to 1/2 tsp baking soda, massage, and let it rest a bit and wash off completely.
Another one is the Japanese method. For 100 gram of shrimp, mix 1/2 tsp salt, 1 tsp potato starch (katakuriko or cornstarch), and 2 T of water. Massage well. This method gets of of griminess of shrimp. After letting it sit for about 5 min, wash off completely before using shrimp. This method also makes very plump tasting shrimp that gives lots of snap to shrimp. Ironchef Chin-san uses this method.
I don't know which method I like best. I should try side by side soon. Do you use any method for shrimp?
I can't use the comment section of Serious Eats for some reason and never post there.