2Hr Aquarist Commentary: Hobbyist nitrate test kits tend to be finicky, while accurate lab grade ones tend to be very expensive. These kits from Seachem , Salifert and Sera will work well enough for hobbyist purposes. Pay attention to the expiry date when using these kits. Livestock waste is the main contribution to NO3 levels in a tank. Some tap water also contain nitrates. Plants constantly uptake nitrates if they are growing. Green dust/spot algae is more easily triggered with high NO3 levels (>10ppm). It is a myth that planted tanks need high NO3 readings to grow well. It is possible to dose say 1ppm of NO3 on a daily basis and get excellent growth despite the residual NO3 reading hitting zero by end of day.
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