How do I raise nitrates?
One of my tanks, a planted Eclipse 12 low-light aquarium, is testing zero for nitrates these days. It's also testing 0 for ammonia and nitrites (which is good).
All my plants were doing terrifically well, but recently, one of my plants has been going a little yellow at the edges. I don't know what it is, but it has long, broad leaves. It's not an anubia.
I'm wondering if this is due to the low nitrate. Shouldn't nitrates be at about 25?
How can I raise my nitrates to a level that is good for plants and still safe for the fish?
I add Seachem Flourish from time to time, but it doesn't have nitrates. It does have some iron.
Any thoughts? Thank you in advance!