I just tested my saltwater in the tank. According to my API test kit, it was 2 DKH, even though i changed water 3-4 days ago. I just beat cyano in that tank, So maybe it's the cause? I went and made a batch of my IO salt to see if it is the salt or API. It tests the exact same. 2 DKH. I tested tap water and it was approx 4-5 DKH. tap water tested higher than fresh saltwater. Is it the salt or API?