How important are Nitrite levels in 10 gallon Aquarium?

Question

Hi, ever since I added some rain water to my aquarium the nitrite level has been between 5 and 10. I've been doing 20 and 25 percent water changes twice a week since but I can't get it to come down. My 2 Neon tetras don't seem to mind. They are happy as ever. My water is very hard, alkalinity is high, ph is high and nitrates are between 20 and 40 which is safe. Everything except nitrites is ok. Before I added the rain water the nitrite level was 0. Any ideas? Thanks in advance to all answerers.

Wow! Thankyou all for the quick responses. I'm really worried now. I have another 10 gallon unplanted tank that I just set up for some new fish I might be getting. Of course, it;s not cycled yet. Should I transfer my Neons to it till I can fix the 1st tank? I'd hate for them to die...

Answer 1

Nitrite levels are very important to the welfare of your fish.They should be ZERO.Keep up the twice a week water changes until they go down to zero. This is especially true given the high pH and hardness numbers that you must deal with. In high pH situations the ammonia remains in a more toxic form. All this sounds terrible,but it really isn't a problem as long as you are diligent on your water maintenance. It may take a few weeks for the bacteria colony that converts nitrites to nitrates to regain it's balance,then you could switch to a less rigorous water change schedule,but I'd try for at least once a week. -----Hope this helps.------PeeTee

Answer 2

Nitrites are rather important in tanks and you don;t want yours to stay elevated for too long. The only real conclusion is that your rain water contains nitrites and the simple answer is to stop using it. If your fish seem healthy and happy in the harder, more alkaline water, then don't worry about that. If you are wanting softer, lower pH water to attempt to breed the neons then I would suggest you buy distilled water to use to cut your tap water. Also, you can add peat moss to the filter to help bring down both the pH and hardness. Between those you should get a soft acidic tank without the added nitrites.

MM

Answer 3

Nitrites can be toxic to fish if the level is too high. Ideally this level should be zero!

My guess is that the rainwater in your area may be somewhat acidic from acid rain. There are two sources for acid rain, SO4 and NOx (either NO or NO2). What the source is depends on where you live. NOx is usually the result of auto exhaust, so I'm guessing you might be downwind from a major metropolitan area.

If your tank has cycled properly, the bacteria should be converting the nitrite to nitrate. Instead of mixing rainwater with your tap water (probably to lower the pH?), try distilled or reverse osmosis (this is the Culligan water that's sold in stores).

Answer 4

Wow, um...Okay, here we go.

Nitrite is more poisonous than ammonia. It emaciates the fish's body and eventually kills them. I wonder if you are using a gravel siphon to do your water changes? Otherwise, you are not removing the waste which produces nitrite.

Neon tetras are rather delicate, which means they will not be able to keep it up for long. I have a few issues with your tank. These are the ideal parameters for a freshwater tetra tank:

pH: 6.8-7.4
kH (alkalinity): 3-10
gH (hardness): 3-10
nitrite: 0ppm
ammonia: 0ppm
nitrate: 0ppm
phosphates: 0ppm

Tetras like soft water, not hard water, and they also enjoy a medium pH (6.8-7.4). If rainwater has this effect on your aquarium, I would find another method of adding water.

Answer 5

Magicman and Copperhead explained it just right and all I have to add is to point out what you've already realized. Your statement, "before I added the rain water the nitrite level was 0" says it all. Clearly, it's the rain water, so go back to what you were doing before.

Answer 6

make the water more acidic for the tetras.