I have a 38 gallon tank its been running for about a year....I had issues with nitrite/nitrate so I got a RenaFilstar XP 2. I keep one back of tank "waterfall" power filter on the tank...The waterfall that hangs on the back has ceramic rings in the bottom and a small amount of floss on the top..Its not really for filter so much as bio filter just to circulate water over the ceramic rings..My Filstar XP has the 30 PPi and 20 PPI pad in the bottom..Ceramic rings and plastic stars in the center for biological and packed with Floss in the top basket and a floss pad on top to keep it in place..
As far as Fish I have 3 Tin Foil Barbs ranging between 6-8 inches..One smaller sized Blood Parrot Cichlid, 1 pink kissing gourami 1 Blue gourami 1 gold gourami and 1 silver dollar ...I also have one Corey Cat to clean the bottom..
My tank is small for the tin foils but I have the oversize filter "filstar XP" and the other for biological filter.
I do 30 40% water changes depending on how often they are done if I go two weeks I usually do around 40% weekly around 30%..
My water usually stays clear no real complaints..I use a API master test kit for fresh water every now and then...
I saw I was getting some algae on my sea shells on the bottom so I added Hagen Waste Control with a few capfuls of API Stress zyme, which I usually add at water changes...I would think my bacteria in my filter should be set in by now, I have been excessively vaccuming the bottom to remove excess food and waste because I have larger fish.
Since the addition of the waste Control I notice my Amonia looks good usually around zero or very little, my Nitrite looks ok zero or close, but my nitrites are just HIGH 180 PPM
even after 30% change it seems high..I am wondering if the waste control would RAISE the Nitrates in excess? I dont have plants in my tank..My tin foils eat them over night..I hate to add the nitrate sock it kills ammonia, and its staying in check on its own..
Just wondering about the nitrates..I pump air in the tank and my fish seem happy and ok swimming as usual, no red gills all fish seem ok..
should I worry or just let it ride for now?