Mixed up 25 gallons of I/O for my weekly water change, FOWLR. Been fighting some hair algae so decided to test the new water and got a positive result for nitrate using the Seachem test kit. I tested my RO/DI water and it shows zero so it must be the salt mix right? Anyone ever have this problem with I/O? Did a search but couldnt find anything. I am thinking of switching to Coralife salt, your thoughts?