I never heard of that so never tested. I dosed 5ppm and saw no issues. Besides in a mature system I would think that ammonia would be quickly dealt with by the nitrogen cycling bacteria already present in the system.Alot of people have reported high amounts of amonia I the calcium nitrate. Some products have a massive amount. I'll purchase some and test and see how I go. I guess it just depends on how much you require to dose
The way I see it is that the vast majority of ingredients is calcium and nitrate. Only a tiny amount is added to the system to achieve the desired level so impurities must be insignificant. I added less than 20ml to 700L of water to achieve the desired nitrate level so I can’t imagine how insignificant the ammonia added would be. I certainly saw no negative effects. Also the LCA product is for aquarium use. Let me know how you go