Is your Bentonite in liquid or powder form? If it is in powder form then you need to hydrate the Bentonite before using it. I never had this problem with liquid Bentonite and I have been making these shakes for many years.
Also instead of using plain water I have used a 50/50 juice-water mixture. It make the shake more palatable .
To hydrate the powdered bentonite mix the 1 teaspoon of the powder with sufficient water to make a “liquidy “ paste somewhat softer than yoghurt and let it sit for a least overnight. I prefer to age it 12 to 24 hrs. I usually mix 3 to 4 tablespoon full of bentonite sufficient for a few days supply.
I hope this helps you. Please read my blog titld “My challenge”, link below.