Super product. Good for aquariums. I use it each time I do a water change. I bought this because my betta fish had a fin rot and was in a very bad condition, after using api aqua salt regularly I was able to help my betta recover and stopped find rot, Now it’s fins are growing back with bright colours. Thanks to api for such an amazing product with clear instructions on it. Very useful product would recommend it highly for all the hobbits who has an aquarium.