sera Nitrite-minus

Immediate help against nitrite

  • removes up to 1.5 mg/l of nitrite per dosage
  • prevents new tank syndrome

Accumulating nitrite (“new tank syndrome”) is a threat during the starting phase of a new aquarium, after a disease treatment or a filter change, since insufficient filter bacteria are present for breaking down toxic nitrite to the plant nutrient nitrate. A nitrite level of 1.0 mg/l can already be harmful for the fish. sera Nitrite-minus provides quick help in case of acute pollution and immediately removes up to 1.5 mg/l nitrite per dosage. It converts toxic nitrite into organic amines that are then utilized by bacteria. sera Nitrite-minus is very well tolerated by ornamental fish, invertebrates and plants, and can be dosed up to 5-fold.


  • removes up to 1.5 mg/l of nitrite per dosage within shortest time
  • prevents new tank syndrome and provides immediate help in case of acute pollution
  • binds nitrite and converts it into organic amines that are utilized by the filter bacteria


Advice: The amount of nitrite in the aquarium water can be checked with the sera nitrite-test (NO2) or the sera Quick Test.


What is a new tank syndrome, when does it occur and what can I do against it? We will answer these and further questions in our contribution “What you should know about the new tank syndrome”.

New tank syndrome course with and without Nitrite-minus

The following chart provides an overview for evaluating the nitrite levels and when measures should be taken:

NO2 Evaluation Measures
0.0 mg/l good -
>0 – 0.5 mg/l action required dose sera bio nitrivec
0.5 mg/l critical possibly dose sera Nitrite-minus (1-fold dosage)
1.0 mg/l harmful dose sera Nitrite-minus (1- fold dosage)
2.0 mg/l dangerous dose sera Nitrite-minus (possibly 2- fold dosage)
5.0 mg/l toxic dose sera Nitrite-minus (possibly 4- fold dosage)

Sufficient for

size sufficient for
50 ml 200 liter / 53 US gal.
100 ml 400 liter / 106 US gal.
250 ml 1.000 liter / 264 US gal.
500 ml 2.000 liter / 530 US gal.
2.500 ml 10.000 liter / 2,640 US gal.
5.000 ml 20.000 liter / 5,300 US gal.


Recommended dosage

Add 5 ml of Nitrite-minus per each 20 l (5.3 US gal.) of water against 1.5 mg/l nitrite. Dose up to 5-fold in case of acute pollution or every other day between the 5th and 15th day during the biological activation. Always check water parameters and ensure good aeration of the water.

Product name SAP-Mat.-Label Content Comment Item no. SAP-Mat.-Number
sera Nitrite-minus Nitrit-minus 50ml D/US/F/NL/I/E/P/.. 50 ml / 1.7 fl.oz. sufficient for: 53 US gal. (200 liters) 32299 45524
sera Nitrite-minus Nitrit-minus 50ml D/US/SI/HR/BG/RO/.. 50 ml / 1.7 fl.oz. sufficient for: 53 US gal. (200 liters) 32299 45525
sera Nitrite-minus Nitrit-minus 100ml US/F 100 ml / 3.38 fl.oz. sufficient for: 106 US gal. (400 liters) 32300 45506
sera Nitrite-minus Nitrit-minus 250ml C/GB/ROK/MY 250 ml / 8.45 fl.oz. sufficient for: 264 US gal. (1,000 liters) 32301 45509
sera Nitrite-minus Nitrit-minus 250ml US/F 250 ml / 8.45 fl.oz. sufficient for: 264 US gal. (1,000 liters) 32301 45516
sera Nitrite-minus Nitrit-minus 500ml US/F 500 ml / 16.9 fl.oz. sufficient for: 530 US gal. (2,000 liters) 32302 45523
sera Nitrite-minus Nitrit-minus 2500ml US/E/P/PL 2,500 ml / 2.5 US qt. sufficient for: 2,640 US gal. (10,000 liters) 32303 45508
sera Nitrite-minus Nitrit-minus 5000ml US/E/P/PL 5,000 ml / 1.3 US gal. sufficient for: 5,300 US gal. (20,000 liters) 32304 45518
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