I wouldn't say that amanos are hardier than any other shrimp species. I've had them die more often than neocaridinas. Test your water parameters first. I keep amanos fine in both 3GH and 1GH both tanks with high nitrates (tap water and too lazy to change my dosing from ADA stuff for the time being). I think stability, oxygenation and bacterial/ecosystem health plays the biggest part in keeping shrimp successfully in addition to their own preferred water chemistry parameters.