Help Nitrit

wazza · Jul 18, 2008

hello just after a bit of advice on nitrit levels is there a safe level . I have a 6x2x2 tank well stocked two 404 filters . PH7.4 , ammonia 0, nitrate 0, but my nitrit 0.1 it said in the test kit that is ok but not sure .Ido a weekly water change about 10 to 20 percent water change and use a gravelcleaner but just worried if it is ok could any one help me thanks wazza.

rhostog · Jul 18, 2008

Have you tested your tap water? Ours contains between 0.1 and 0.2 nitrite - took me ages to work out why I couldn't get to zero in the tank when I kept doing water changes to try to bring down the level... In the UK, drinking water is allowed to contain nitrite levels up to 0.5 (not sure where you're located).

While your level is very low, I'd be more worried that this is a symptom of a problem. I'd suggest testing your tap water, and if that's not the source, hopefully someone more knowledgeable than me can help...

Corleone · Jul 19, 2008

How long has the tank been set up, what's in it? NitrAte of 0 is unusual, but not impossible. Generally there isn't a safe level for nitrite (except 0), but it's not as bad a killer as ammonia, provided it isn't a long term problem. The advice given in the new to the hobby forum for people in fish-in cycles is to keep it under .25 at all times, but it sounds like it's there anyway.

Is this an ongoing problem, or just an intermittent blip? If it's a one-time thing, you could have tested at a bad time (maybe all your fish pooped at the same time or something), or there could be some food or a dead snail rotting in the substrate, or maybe a mini-cycle if you recently did a major filter cleaning. If it's ongoing, then like rhostog said, it could be a symptom of something else wrong.

wazza · Jul 19, 2008

thanks for your help the tank is about 8 months old so it is not that .I have tested tap water befor and i know it is high in nitrite but i use asafe water conditioner what is surpost to work and abio cultures . TESTEDwater for ph etc and all ok apart from nitrite.WILL water changes get rid of it because i will allways have this level should i do a 50 percent water change i am worried i dont kill my l66/ l18 /l75 plecos with a big water change all will they be ok had them four weeks .Will the level of nitrite be safe if left .By the way i live in liverpool thanks wazza

Corleone · Jul 19, 2008

If there's nitrite in the tap water, chances are you'll just be maintaining the level by doing more water changes.

Water changes won't remove a meaningful amount of bacteria. The bacteria live on surfaces, particularly in the high flow enviornment of the filter, not free floating.

rhostog · Jul 19, 2008

Most water conditioners do not remove nitrIte - I believe Amquel Plus does, and there may be others - but most just do chlorine, chloramine, heavy metals. But the bacteria in your filter should be able to cope with the nitrite long-term. In my (limited!) experience, they're quite slow to kick in, and take a few days to reduce it to zero after a blip.

As Corleone says, if you do a large water change, you'll just be adding more nitrite from your tap water. Large water changes are probably best avoided unless the nitrite level in your tank gets higher than in your tap water.

I have nitrite in my tap water, so I do twice-weekly small water changes (about 10%) - this means my nitrite levels never get above a trace, but I'm still refreshing the tank water. I'd suggest that's probably the best solution for you, to do frequent small water changes (you might get away with less than me as your tank is more mature), and make sure you don't over-feed or over-stock. If it becomes a problem, you could consider RO water, but that's extra cost and hassle...

Hope it sorts itself out soon, and good luck with the plecos.

wazza · Jul 20, 2008

rhostog said:
Most water conditioners do not remove nitrIte - I believe Amquel Plus does, and there may be others - but most just do chlorine, chloramine, heavy metals. But the bacteria in your filter should be able to cope with the nitrite long-term. In my (limited!) experience, they're quite slow to kick in, and take a few days to reduce it to zero after a blip.

As Corleone says, if you do a large water change, you'll just be adding more nitrite from your tap water. Large water changes are probably best avoided unless the nitrite level in your tank gets higher than in your tap water.

I have nitrite in my tap water, so I do twice-weekly small water changes (about 10%) - this means my nitrite levels never get above a trace, but I'm still refreshing the tank water. I'd suggest that's probably the best solution for you, to do frequent small water changes (you might get away with less than me as your tank is more mature), and make sure you don't over-feed or over-stock. If it becomes a problem, you could consider RO water, but that's extra cost and hassle...

Hope it sorts itself out soon, and good luck with the plecos.

Thanks alot for your advice iwll try to sort it out now thanks once agian wazza