Bio balls, Rings, + Stars are by design a nitrate factory it's what they do - they house and grow Aerobic bacteria, bacteria that thrives in well oxygenated water. Aerobic bacteria converts ammonia to nitrite and nitrite to nitrate - hence nitrate factory - it expels it. Anaerobic bacteria lives in oxygen deficient areas like in and under substrate or deep within rockwork. Anaerobic bacteria converts Nitrate to harmless nitrogen gas which is then expelled from the system were oxygen enters - hence the nitrogen cycle.
.025 ammonia's still deadly - what are the Nitrites???? they are just as deadly as ammonia and if both ammonia and nitrate are present nitrite will probably be present as well.
Diatoms thrive in waters high in silicates - the silicates leach into the water via sand, aragonite, and rockwork. They are also added when we change or top off the water. However there is no one single source for the outbreak, diatoms aren't very reliant on light more so nitrogenous material being produced in large quantities via cycling. This is called " New Tank Syndrome"
