Brown blood disease occurs in fish when water contains high nitrite concentrations. Nitrite enters a fish culture system after feed is digested by fish and the excess nitrogen is converted into ammonia, which is then excreted as waste into the water. Total ammonia nitrogen (TAN; NH3 and NH4+) is then converted to nitrite (NO2) that, under normal conditions, is quickly converted to nontoxic nitr...
I have tried everything for lowering Nitrite and Nitrate levels in my 60 gallon tank with four Koi's. it's been 3 weeks now and nothing is bringing down the levels. I'm monitoring feeding amounts, salt treatment, water changing, gravel vacuuming. Fish are showing no signs. What next? Thank You, Robert.