I have a fairly new 30 gallon(UK) tall tank with 4 zebra danios, 4 glow tetras and 10 very small cardinals.
Water specs: Temp 25C, pH about 8, Ammonia less than 0.1mg/l, Nitrite less than 0.1mg/l, Nitrate about 10mg/l
I have been managing the nitrate levels by 25-30% water changes every 2-3...