Tank Nitrites, FW    8/5/07 Hi, Dave here. I have 2 running tanks. A 47 gal with 1 Bala shark, 1 Redtail shark, and 2 Plecos. The 55 gal has 1 Oscar, 1 Dempsey, 1 Raphael cat and 1 Bala shark. All levels on the 47gal are fine and tank was never cycled before fish were put in. In my 55 gal tank all levels are fine except for the nitrite. I vacuum the gravel in each tank once a week, and change anywhere from 10-15 gallons of water adding water conditioner every time) during that process for both tanks. For some reason the nitrite levels in the 55gal wont go down. I bought a Nitra-Zorb pack last week and have started to do a 10 gal water change every night but no change. Thank you very much for your help. >>>Greetings, Jim here. You should never fully stock a freshwater tank until the ammonia and nitrite levels have dropped to zero. Every tank cycles differently - some take longer than others. You didn't mention how long the 55 gallon had been running, what kind of filtration you have, etc. Be patient. Jim<<<

Nitrate & Nitrite in an Uncycled FW Tank - 4/24/2006 Hi <<Hi Gary.>> I was hoping you could help me. <<I'll try!>> I have got a nitrate/nitrite problem.  I have recently started a freshwater fish tank.  Everything was going ok, took the advice of where I bought my tank, read up a few books, and I set the tank up. <<Many fish stores are less than properly educated.>> Then added the water with a water conditioner also bacteria, I left it a few days then added plants and rocks. <<If you added live bacteria, like Bio-Spira (anything else available is dead bacteria at best), it will have died in a day or so without ammonia from fish wastes to feed it.  You add your fish right after adding the Bio Spira to your filter.>> I then also left a few days longer approx 4 days, after checking ph levels, ammonia, nitrate, nitrite, calcium hardness and carbonate hardness all seemed to be ok. <<You didn't read ammonia, nitrite or nitrate because your tank hadn't yet started cycling.>> I went and bought my fish a couple of days later and I noticed most of my fish had white spot so I treated that problem with tri sulfa tablets (treated twice).  This is when all my problems now have started the ammonia nitrate & nitrite levels went sky high so I started to do the water changes.  I have now just got the ammonia level down to 0ppm but the nitrate & nitrite are just getting worse. <<Your tank was not cycled, and now is.  Do daily water changes of 75% or more to keep these toxins down while the nitrifying bacteria grow in your filter.>> I suppose you can tell from this that I am inexperienced in aquarium keeping, but I do enjoy fish keeping.  I hope you can help me with this problem, as I am getting more worried about losing my fish.   <<Keep up with the water changes, and your tank should be cycled in a few weeks.  Read on WWM to learn about fishless cycling for the future.>> I look forward to hearing from you soon Thanks, Gary <<Glad to help. Lisa.  In the future, please capitalize your I's and run your email through a spelling/grammar checker.>>

Lowering Nitrite 8/3/05 How  harmful is a high nitrite n02 and how can I lower it. < Ammonia is the most toxic form of fish waste. It is then converted by bacteria to a less toxic form of waste called nitrite. Bacteria then convert it one more time to an even less toxic waste called nitrate. In a new tank it takes about 2 weeks for the bacteria to get established and convert the ammonia. In another two weeks the bacteria are then established to convert the nitrite to nitrate. Different fish have different tolerances to nitrite. Some FW riverine species have zero tolerances while others don't seem to be affected at all. The toxicity is also affected by the pH. Lower pH's make these compounds less toxic. Reduce nitrites by reducing the waste. Don't overfeed, vacuum the gravel and clean the filters. Some chemicals will actually tie up nitrites. I am not too sure what the long term affects will be. Go to Marineland.com and check out Dr. Tim's Library for lots of articles on nitrification.-Chuck>