How long does nitrite take to convert into nitrate?

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momsspaghett

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Hello. Yesterday around noon I completely cleaned out my tank (about 85-90% water change) which hadn't been deep cleaned in about 2 months, only one fish in it, an oto. I do 25% water changes/adding water to the tank about every other week when the water level goes down. My water paraments prior to cleaning were .25-50 ppm ammonia, 0 nitrite, and a whopping 40 ppm nitrate. I read a few opinions on having high nitrate in planted tanks but I never understood if having 20+ppm nitrate was good for the tank. After 24 hours from the water change, the ammonia read 0-.25ppm, .50-1.0 ppm nitrite and 10 ppm nitrate. My question is, approximately how long would it take for nitrite to convert completely in an old established tank? And is denitrate/matrix necessary to use? I don't want to have high nitrate levels like I did previously but again, I am not certain if it is ok to have such levels. I am planning on getting some floating plants and possibly adding some safe start to the tank. Two older sponges from previous tanks are in the filter along with quarts rings. I never really "restart" tanks but I have done 50-75% water changes and the paraments usually remain the same.
 
This is 100% off topic but for some reason reading the title of this thread i read "how long does nitrate take to turn into spaghetti" I was very confused and I have no idea why I read it like that
 
Are there live plants now, or have there been until now?

To the issue of nitrate...nitrate is toxic to fish. The damage can probably best be described by saying that nitrate slowly weakens the fish, and this in turn causes other issues that the fish would otherwise be able to easily handle. There is not a lot of scientific evidence with respect to direct disease/problems from nitrate on aquarium fish (there is more on food fish), but there is increasing evidence that nitrate is likely responsible for some cichlid issues like hole in the head, and if memory serves me, Malawi bloat. The extent to which nitrate will likely harm fish depends upon the level, the exposure time, and the species. Cichlids are now known to be quite sensitive to nitrate at or above 20 ppm. When we realize that none of the fish species we maintain in our tanks are exposed to nitrate in their habitat waters, or if nitrate is detectable it is not going to be anywhere even remotely close to 3 ppm and never higher, it should be obvious that keeping nitrate as close to zero as possible will inevitably be better for the fish.

Another point is the source water. Have you tested this for nitrate, and if so, what was the number? Nitrate entering with fresh water is one distinct issue, different from nitrate occurring within the biological system. The latter is much easier to deal with, because we know the causes of nitrate in an aquarium and can work to eliminate them.

The ammonia and nitrite you mention are likely due to the disturbance of the substrate. I asked about live plants because normally these take up much if not all of the ammonia that is produced regularly by fish and decomposition, so the AOB/AOA (ammonia oxidizing bacteria/archaea) are fewer, and the next stage of NOB/A (nitrite oxidizing bacteria/archaea) minimal, so it takes time for these to reproduce if ammonia or nitrite suddenly increases. NOB can reproduce roughly every 30 hours, and they do this by binary division. However, if the ammonia is high, this thwarts the reproduction of the NOB, and can even kill them.
 
bruh that is hilarious
Oh my goodness I know why now, it's because of your username! I must have seen it and my mind fused the two together :rofl:
 
Are there live plants now, or have there been until now?

To the issue of nitrate...nitrate is toxic to fish. The damage can probably best be described by saying that nitrate slowly weakens the fish, and this in turn causes other issues that the fish would otherwise be able to easily handle. There is not a lot of scientific evidence with respect to direct disease/problems from nitrate on aquarium fish (there is more on food fish), but there is increasing evidence that nitrate is likely responsible for some cichlid issues like hole in the head, and if memory serves me, Malawi bloat. The extent to which nitrate will likely harm fish depends upon the level, the exposure time, and the species. Cichlids are now known to be quite sensitive to nitrate at or above 20 ppm. When we realize that none of the fish species we maintain in our tanks are exposed to nitrate in their habitat waters, or if nitrate is detectable it is not going to be anywhere even remotely close to 3 ppm and never higher, it should be obvious that keeping nitrate as close to zero as possible will inevitably be better for the fish.

Another point is the source water. Have you tested this for nitrate, and if so, what was the number? Nitrate entering with fresh water is one distinct issue, different from nitrate occurring within the biological system. The latter is much easier to deal with, because we know the causes of nitrate in an aquarium and can work to eliminate them.

The ammonia and nitrite you mention are likely due to the disturbance of the substrate. I asked about live plants because normally these take up much if not all of the ammonia that is produced regularly by fish and decomposition, so the AOB/AOA (ammonia oxidizing bacteria/archaea) are fewer, and the next stage of NOB/A (nitrite oxidizing bacteria/archaea) minimal, so it takes time for these to reproduce if ammonia or nitrite suddenly increases. NOB can reproduce roughly every 30 hours, and they do this by binary division. However, if the ammonia is high, this thwarts the reproduction of the NOB, and can even kill them.
I have had these plants in there for over a year or so, this tank has been running well over 2 years. Good thing I am not interested in keeping cichlids anytime soon. Since there is only fish in the tank, I haven't been feeding it all too much, occasionally half algae wafers which last it 2-4 days. Nitrate in my tap was 5-10ppm, light orange tone. This is the tank itself, always will add more plants to it whenever I can so I am guessing the substrate debris that was in there before this complete clean caused a lot of that ammonia build up. There's only one fish in there so there would be no decomposition of other fish, the pest snails could be a concern but, I wouldn't think they have much bioload. I want to add shrimp to this tank and I would think they wouldn't be causing much ammonia either. So adding safe start or one and only would help speed up that process because of the large water change. Ammonia isn't too high as of now.
 

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In a healthy established aquarium, ammonia from feeding the fish a normal amount, can be converted into nitrite within 30-60 minutes. The same deal with nitrite into nitrate, around 30-60 minutes.

If the ammonia or nitrite levels are really high, it can take longer, up to 12 hours or more, depending on the level.

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De-nitrating substances are not necessary and most don't work in aquariums because there is too much oxygen in the water and the de-nitrating bacteria are anaerobic. They die if exposed to oxygen. If you have enough oxygen in the water for fish to live, the anaerobic bacteria cannot live.

You want to keep ammonia and nitrite on 0ppm at all times, and nitrate under 20ppm at all times. All 3 (ammonia, nitrite & nitrate) are toxic to all major life forms including people, animals, birds, reptiles and fish. So keeping their levels as low as possible is the safest thing to do.

If you have lots of live aquarium plants and floating plants in the tank, they will use ammonia and help keep all the 3 levels down. You still need to do water changes, but lots of plants in a tank will keep the water cleaner for longer.

Water Sprite (Ceratopteris thalictroides/ cornuta) is a nice floating plant that grows in most aquariums. It helps keep the water clean, provides shelter for fish, and can be planted in the substrate or grown on the surface.
 
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I have had these plants in there for over a year or so, this tank has been running well over 2 years. Good thing I am not interested in keeping cichlids anytime soon. Since there is only fish in the tank, I haven't been feeding it all too much, occasionally half algae wafers which last it 2-4 days. Nitrate in my tap was 5-10ppm, light orange tone. This is the tank itself, always will add more plants to it whenever I can so I am guessing the substrate debris that was in there before this complete clean caused a lot of that ammonia build up. There's only one fish in there so there would be no decomposition of other fish, the pest snails could be a concern but, I wouldn't think they have much bioload. I want to add shrimp to this tank and I would think they wouldn't be causing much ammonia either. So adding safe start or one and only would help speed up that process because of the large water change. Ammonia isn't too high as of now.

The plants would easily take up any ammonia normally occurring (without creating nitrite), so as I previously suggested, the sudden ammonia and nitrite was the substrate disturbance.

When you have live plants as here, you do not want to be thwarting them by encouraging nitrifying bacteria so on that basis I would not add SafeStart or the One and Only. Aquatic plants can take up a considerable amount of ammonia/ammonium, especially fast growing species (floaters are "ammonia sinks"). If this were me, I would do another water change or two, with a good clean of the substrate since it has now been disturbed, then monitor.
 
The plants would easily take up any ammonia normally occurring (without creating nitrite), so as I previously suggested, the sudden ammonia and nitrite was the substrate disturbance.

When you have live plants as here, you do not want to be thwarting them by encouraging nitrifying bacteria so on that basis I would not add SafeStart or the One and Only. Aquatic plants can take up a considerable amount of ammonia/ammonium, especially fast growing species (floaters are "ammonia sinks"). If this were me, I would do another water change or two, with a good clean of the substrate since it has now been disturbed, then monitor.
Would you recommend using products which reduce nitrate such as matrix/denitrate? And what percentage of water changes, mainly for cleaning the substrate?
 
Would you recommend using products which reduce nitrate such as matrix/denitrate?

That depends. I would neve use these products if the nitrate is solely occurring within the aquarium because that indicates a problem and can be resolved easily (don't overstock, don't overfeed, regular water changes, live plants). Nitrate in the source water is another issue, and if it really is around 10 ppm or higher, it might be advisable to take action. For this, I refer you to another member here who has conquered his serious nitrate in the water problem, @AbbeysDad . There are articles on his blog,

And what percentage of water changes, mainly for cleaning the substrate?

Provided the parameters (being GH, pH and temperature here) are reasonably the same between tap water and tank water, you cannot do any harm with larger or more frequent water changes. So, I would do a 70% once weekly as normal, more frequently to deal with issues.
 
If you have a nitrite reading, the nitrate test kit will pick up the nitrite and read it as nitrate and give you a false reading. If you have 1ppm nitrite, you might not have 10ppm nitrate, it should be less.

Check the water again in 24 hours and if there is no nitrite, then check the nitrate and see how high it is.
 
And is denitrate/matrix necessary to use? I don't want to have high nitrate levels like I did previously but again, I am not certain if it is ok to have such levels.
I come to this 'party' late and only after my friend Byron mentioned me above. As Byron pointed out, my articles should help, but I want to address the above question....
Seachem Matrix and De*Nitrate is merely pumice (lava rock) stone. The claim is that it has micro pores that will support anaerobic bacteria to convert nitrates into nitrogen gas that will harmlessly escape into the atmosphere. As my one article points out, I tried using Matrix and De*Nitrate in a few different configurations, but I was NEVER able to see a noticeable reduction in tank nitrates. So I simply can't recommend either product for nitrate reduction.
From reading your post, I think with plants, especially fast growing floating plants and an increase in your volume/frequency of partial water changes and your 'problems' will disappear. There are of course different schools of thought, but when in doubt, I like 50% weekly water changes. In general, there's no such thing as too much fresh, clean water! :)
 
The claim is that it has micro pores that will support anaerobic bacteria to convert nitrates into nitrogen gas that will harmlessly escape into the atmosphere.
As a follow-up, I might point out that micro pores in pumice maybe nearly pointless as they can pretty quickly become coated/plugged with detritus making them ineffective at housing beneficial anaerobic/anoxic bacteria - but it is marketing genius. Oh and these products are rather high priced compared to companies that sell various sizes of pumice products for gardening purposes. I'm also not convinced that Purigen collects waste before it decomposes and pollutes the water. (love the company, but these products, not so much). :)
 

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