Cycling:
When setting up a new aquarium it is important to first complete a thorough cycling so that the beneficial bacteria needed for ammonia and nitrite conversion can be established. In a mature aquarium it is important not to over clean the bacterial environment to maintain a healthy level of nitrogen cycling. Once nitrifying bacteria is present it can begin to metabolize the harmful ammonia produced by decaying plants, uneaten food and decomposing fish waste.
Process:
As previously stated ammonia is produced by decaying plants, uneaten food and decomposing fish waste. One group of bacteria’s purpose is to convert the ammonia by binding it with water and the resulting chemical is nitrite. This is when another group of bacteria does its job. They take the nitrite and bind it with water forming the chemical nitrate. The presence of ammonia and nitrites are extremely toxic to fish while nitrate levels are less toxic unless harmful levels occur. By using a master test kit found in any aquatic retail store, you can test your aquarium water levels to check for the presence of these harmful chemicals. Frequent partial water changes can help prevent nitrates from collecting in harmful amounts in the aquarium.
pH levels:
The pH of aquarium water can affect ammonia levels greatly. Water will contain two forms of ammonia: pure NH3 and the ammonium ion NH4+. Ammonia in its pure chemical state is more toxic than the ammonium ion, but both still pose a threat to the lives of your fish. Highly alkaline water contains higher amounts of pure ammonia while slightly acidic water contains higher amounts of the ammonium ion. The difference in the chemistry of the two substances is minuscule but the affects can make all the difference in the health of your fish. It is a known fact that ammonia poisoning is more common at high alkaline pH levels.
Ammonia:
Ammonia (NH3) is a chemical that is highly toxic to fish even in small amounts. Ammonia toxicity causes severe stress to fish making them more susceptible to disease and death. This chemical also causes damage to gill membranes and inhibits normal respiratory function. It is important to test the aquarium regularly for this chemical; once a month if your tank is healthy but more often if there are signs of sickness or death. When using a testing kit ammonia traces should be undetectable in your results. The test results are measured in ppm or parts per million and your results should ideally read 0ppm. If any traceable amounts are present there are ammonia converting chemicals that can be found at aquatic retail locations. This chemical doesn’t remove ammonia from the water but it helps to convert the highly toxic form into a less toxic version allowing it to be oxidized through a bio-filtration system. Carbon can also be used in the filtration process to help remove ammonia to improve water quality. It is important to check daily to see if your filter is clean and running properly. If a filter gets too dirty or breaks down it could result in the presence of toxic ammonia in the tank. Take special care to not over feed the fish not only for their well-being but also because this is important in aquarium maintenance and filtration care. Do not overstock the aquarium because more fish mean more waste. When using medications be sure to test water levels because bacteria can be sensitive to foreign chemicals resulting in the inability to oxidize ammonia. It is important to clean the aquarium regularly but it is also very crucial to remember not to over clean the bio-filter. This mechanism plays an important role for the bacterial population in the aquarium, without which the nitrogen cycle cannot take place.
Nitrite:
When the ammonium ion (NH4+) is mixed with water the beneficial bacteria can then convert the ammonia into nitrite (NO2-). Much like ammonia, nitrite is also toxic and can be harmful towards fish. If traces of nitrites are in the aquarium it can cause severe stress to the fish. This leads to respiratory hardship and a weakened immune system, which makes the fish more susceptible to disease and death. To prevent this from happening you must be sure to test for nitrite periodically just as you would for ammonia. When testing for ammonia, having a result of 0ppm is not an indication of what your test results should be for nitrite or nitrate. It is very important to test for each substance individually as part of your routine aquarium maintenance.
Nitrate:
When the substance nitrite (NO2-) mixes with water the beneficial bacteria can then convert the nitrite into nitrate (NO3-). This substance called nitrate is seemingly harmless towards fish but in higher concentrations it is not. Unlike ammonia and nitrite, nitrate can be present in the aquarium as it usually is to a certain extent. In the past it was believed to be harmless towards fish but studies show that the over concentration of this chemical in the aquarium can have adverse effects on the health and wellness of fish. If there is an over abundance of nitrate in the tank it could be an indication that there is too much fish and plant waste. If not dealt with properly, this problem will inevitably lead to diseased, unhealthy fish. Another consequence of too much nitrate is algae. Nitrates promote the growth of algae which can result in a cloudy tank with increasing amounts of the toxic ammonia and nitrite. This is why it is so important to test for nitrate even though it’s ok to have a slight amount in the aquarium. Your nitrate test results should be 40ppm or less, the lower the better. If your nitrate test results show that excessive amounts are present there are several ways to remove enough nitrates for the aquarium water to be safe once again. Partial water changes should be performed at once if the levels are exceedingly high. A tap water filter can be used to remove all chemicals from the water including ammonia, nitrite and nitrate. If this does not produce satisfactory results you might want to try a nitrate removing filter.
Fishless Cycling:
As stated before, aquarium cycling is a very important step in starting a new aquarium. Without the beneficial bacteria present to break down ammonia and nitrite the first tank residents will most likely not survive. A method called fishless cycling was created to start new aquariums without risking the lives of the first fish to live in it. This method is also a quicker route to forming the much needed bacteria. It takes up to three weeks instead of up to 6 weeks. When a tank is set up pure ammonia is added to the water. Additional doses of ammonia are added each day and daily tests are done to monitor ammonia levels. Once the bacteria for breaking down ammonia is established you’ll see the ammonia test results quickly drop to 0ppm. Continue adding slight amounts of ammonia daily to give the nitrite levels a chance to go up. The presence of nitrite will bring about new beneficial bacteria whose purpose is to deal with the conversion of nitrite to nitrate. Once the water test results show traces of nitrate, do one more partial water change, wait awhile and then test again for ammonia, nitrite and nitrate. If the results of the tests are favorable you are now ready to stock your tank with new fish. The new fish waste will be the source of ammonia needed to continue the nitrogen cycle.
Tips on how to safely clean your aquarium:
Once you have established a colony of beneficial bacteria you do not want to harm it. Cleaning your aquarium is essential to the good health of your fish but keeping all of those good bacteria is just as important. This is why it is essential to do partial water changes. Keeping some old water in the tank at all times will give the bacteria that are still present a chance to multiply and replenish. Full water changes will wipe out too much of the bacteria which may allow a spike in ammonia and nitrite levels resulting in possible death. Another important thing to remember is not to use any cleaning chemicals that do not specify safe for use in aquariums. Bacteria are very sensitive to chemicals and you would not want to kill your colony of beneficial bacteria. If you need to clean any filter cartridges, it is a good idea to rinse them in the water removed from the aquarium because this water already contains the bacteria.
Water test results:
I used two different aquariums to perform a series of tests on. The test results show the difference in pH, ammonia, nitrite and nitrate levels of a healthy tank to an unhealthy tank. Here you can see what the test results of an acceptable tank looks live versus the test results of an unacceptable tank.
In “tank A”, partial water changes were performed every 3 days, the fishes were fed as recommended on the food label and the tank was not overstocked with fish. The pH, ammonia, nitrite and nitrate levels were tested and the results proved it to be a healthy tank.
| Tank A | |
 pH level 7.6 |  Ammonia level 0ppm |
 Nitrite level 0ppm |  Nitrate level 5ppm |
In “tank B”, no water changes were performed for 2 weeks, the fishes were overfed according to the recommendations on the food label and the tank was overstocked with fish. The pH, ammonia, nitrite and nitrate levels were tested and the results proved to be unhealthy by the recommended standards.
| Tank B | |
 pH level 7.0 |  Ammonia level 0ppm |
 Nitrite level .25ppm |  Nitrate level 50ppm |
| Tank A | Tank B | Optimum levels | Analysis | |
| pH | 7.6 | 7.0 | Between 7.0 and 7.6 | The pH levels for both aquariums are within the acceptable parameters. |
| Ammonia | 0ppm | 0ppm | 0ppm | The ammonia levels for both aquariums are at the acceptable level. |
| Nitrite | 0ppm | .25ppm | 0ppm | Tank A is healthy and has no detectable nitrite. Tank B shows the presence of nitrite which is not acceptable. Immediate maintenance should be performed on tank B. |
| Nitrate | 5ppm | 50ppm | Below 40ppm | Tank A is healthy and contains nitrate within acceptable parameters. Tank B contains levels which exceed the acceptable amount. Immediate maintenance should be performed on tank B. |
Using a master test kit in your regular aquarium maintenance routine can prove to be very useful. By detecting harmful chemicals early you can take action to prevent unhealthy conditions in your tank. Doing what is necessary to maintain healthy water levels in your aquarium will allow you to enjoy the company of your fish for a long, long time.
Citations
thetropicaltank.co.uk
northcoastmarines
API Freshwater Master Test Kit Instruction Booklet
malawicichlids
Another useful article on the web
- pH and Ammonia at nippyfish.net!
16 comment(s)
Chris OE on January 7, 2010, 10:14 pm wrote
I like this article a lot. So often people feel like if the ammonia is at zero then things are fine. They don’t understand that nitrite and nitrate are real problems, just because they won’t cause instant death. I am in the process of cycling a 55 gallon (could not find ammonia with no additives, so I am stuck with long slow cycling) and just finally in the nitrite stage. I appreciate having this information available.
I like this article a lot. So often people feel like if the ammonia is at zero then things are fine. They don’t understand that nitrite and nitrate are real problems, just because they won’t cause instant death. I am in the process of cycling a 55 gallon (could not find ammonia with no additives, so I am stuck with long slow cycling) and just finally in the nitrite stage. I appreciate having this information available.
denverfishmonger on January 17, 2010, 8:56 am wrote
If I have several tanks with 0 nitrIte, but plenty of nitrate, what’s the problem, and what’s the course of action? The fish seem happy & healthy.
If I have several tanks with 0 nitrIte, but plenty of nitrate, what’s the problem, and what’s the course of action? The fish seem happy & healthy.
Answer: The relation between nitrites and nitrates is described above. Sometimes the reactions are too fast and nitrites are eliminated to nitrates immediately. High level of nitrates isn’t too dangerous. If you want to get rid of it, simply add another filter or use nitrate removing filters. It’s all mentioned in the article above.
Bradley on March 10, 2010, 11:56 pm wrote
I have a 300 gallon aquarium that is 7 months old. At the 6 month mark my "nitrate" levels started climbing. In two weeks it reached 40 and for the last two weeks it has reached 80. All other readings are normal. I have two FX5 canister filters and have added the Fluval nitrate remover to these canisters. It is supposed to work or lower the amount in hours, I have had it for two days now and in the morning I get a reading of 15 but by noon I get a reading of 40. The fish are flashing but there is not other sign of illness. I have been doing water changes but I am not getting anywhere with this issue. I do not understand since there was no problems for the first 6 months. Any ideas?
I have a 300 gallon aquarium that is 7 months old. At the 6 month mark my "nitrate" levels started climbing. In two weeks it reached 40 and for the last two weeks it has reached 80. All other readings are normal. I have two FX5 canister filters and have added the Fluval nitrate remover to these canisters. It is supposed to work or lower the amount in hours, I have had it for two days now and in the morning I get a reading of 15 but by noon I get a reading of 40. The fish are flashing but there is not other sign of illness. I have been doing water changes but I am not getting anywhere with this issue. I do not understand since there was no problems for the first 6 months. Any ideas?
Answer: The problem may lay in the substrate; If the substrate is oversaturated with excrements, this could be the problem.
Pablo, of Surrey, B.C. Canada on April 16, 2010, 8:49 am wrote
I keep a dozen - 2 & 1/2" size discus fish in a 45 gal. planted display tank. The fish are thriving & water is maintained in pristine condition: Temp. 86 F; pH 7.0; ammonia, nitrite & nitrates are always maintained @ 0. Water is kept crystal clear - by regular weekly cleaning of tank, filters, & gravel, along with min. 25% water changes every 3 days, and use of Chemi-Pure filter media. Only very minute traces of algae are present & plants are in excellent condition. Tips for those with any ammonia, nitrate, cloudy water, algae, etc. problems - no large secret: Frequent large changes of good, treated tapwater, filter cleanliness, & Dick Boy’d Chemi-Pure product. P.S. Also try ( you ’cut them to size’ to fit your filter) forest green, multi-purpose fine fibre scrubbers - buy them in bulk at your local dollar store, as one of your filter media. They’re superb for removing all manner of fine detritus. Rinse them well first, and layer them up, 3 or 4 pads together.
I keep a dozen - 2 & 1/2" size discus fish in a 45 gal. planted display tank. The fish are thriving & water is maintained in pristine condition: Temp. 86 F; pH 7.0; ammonia, nitrite & nitrates are always maintained @ 0. Water is kept crystal clear - by regular weekly cleaning of tank, filters, & gravel, along with min. 25% water changes every 3 days, and use of Chemi-Pure filter media. Only very minute traces of algae are present & plants are in excellent condition. Tips for those with any ammonia, nitrate, cloudy water, algae, etc. problems - no large secret: Frequent large changes of good, treated tapwater, filter cleanliness, & Dick Boy’d Chemi-Pure product. P.S. Also try ( you ’cut them to size’ to fit your filter) forest green, multi-purpose fine fibre scrubbers - buy them in bulk at your local dollar store, as one of your filter media. They’re superb for removing all manner of fine detritus. Rinse them well first, and layer them up, 3 or 4 pads together.
Patti on April 27, 2010, 10:45 pm wrote
I’m not sure what my tank is doing in terms of cycling. We’ve had the tank for 2 months and added a few danios to get things started. We got the spikes and it looked like the tank had cycled. Three weeks ago we bought 2 red platies just to be sure that our tank could handle an addition successfully. pH is 7.6, ammonia is .25, nitrite is 0, and nitrate is 5. We’ve been doing 20% partial water changes each week and vacuuming 20% of the gravel. We add stress coat when we do water changes. One of the platies died two days ago. He was gasping but was the only fish doing that. He also had a white spot on one side a bit under the eye. This spot was not present when we first got him. When I first saw his white spot, I treated the aquarium with aquarium salt. I used 1/2 cup per 40 gallons which is on the low side because of the plants. Our other fish are fine. They are active and eating energetically at feeding time. We have a densely planted aquarium, roughly 3.5 watts of light per gallon and a CO2 system. Our plants are doing fine. When we got the platies, we had a bunch of algae on our plants. The platies ate the algae which was fine by me. With the ammonia at .25, I’m just not sure what is going on with our aquarium. I was thinking of waiting a few weeks to see what happens while continuing the water changes as I have been. What do you think? We eventually want to add more fish but I am hesitant to add fish when one of the cheap fish died and my ammonia is high. What should I do?
I’m not sure what my tank is doing in terms of cycling. We’ve had the tank for 2 months and added a few danios to get things started. We got the spikes and it looked like the tank had cycled. Three weeks ago we bought 2 red platies just to be sure that our tank could handle an addition successfully. pH is 7.6, ammonia is .25, nitrite is 0, and nitrate is 5. We’ve been doing 20% partial water changes each week and vacuuming 20% of the gravel. We add stress coat when we do water changes. One of the platies died two days ago. He was gasping but was the only fish doing that. He also had a white spot on one side a bit under the eye. This spot was not present when we first got him. When I first saw his white spot, I treated the aquarium with aquarium salt. I used 1/2 cup per 40 gallons which is on the low side because of the plants. Our other fish are fine. They are active and eating energetically at feeding time. We have a densely planted aquarium, roughly 3.5 watts of light per gallon and a CO2 system. Our plants are doing fine. When we got the platies, we had a bunch of algae on our plants. The platies ate the algae which was fine by me. With the ammonia at .25, I’m just not sure what is going on with our aquarium. I was thinking of waiting a few weeks to see what happens while continuing the water changes as I have been. What do you think? We eventually want to add more fish but I am hesitant to add fish when one of the cheap fish died and my ammonia is high. What should I do?
Answer: You haven’t mentioned anything regarding size of the aquarium and filtration. Installing additional filter will help. Also bear in mind that if one fish dies, it doesn’t mean that other will follow the that first one. When fish keepers introduce new fish, not all survive the first month or two. I’d say it’s not rule, but it is very usual. It happens even in 100% cycled aquariums.
gemma on May 25, 2010, 4:17 am wrote
My 24 gallon tank has been set up nearly 3 weeks, the ammonia is high like 2 or 3, and both the nitrite and nitrate is high. I have 5 fish, about 4 inches each. I have an internal filter on each side of the tank. First is an aquaone 101f and the other is a fluval 2. I have carbon in the fluval 2. My fish seem OK, but I’m doing water changes every 2 days, I use the aqua safe for the tap water, and I’m using stress zyme, someone told me to get the temperature up to 78-80 Celsius to speed up the good bacteria growth. I’m just wondering if I should take 2 fish out and put them in my 35 liter tank that has been sitting fishless for 2 weeks with an internal filter on, maybe separating them will bring the ammonia down and then when it has finished cycling, I can add the fish back to the big one, because I plan to put tropical in to the 35 liter tank, but I want 2 get bused to using the heater on it. When I get my big one sorted then I do the tropical. But as far as the big tank goes I think I’m going to have to be patient and hope my fish don’t die. Any suggestions will be great! Thanks, kind regards.
My 24 gallon tank has been set up nearly 3 weeks, the ammonia is high like 2 or 3, and both the nitrite and nitrate is high. I have 5 fish, about 4 inches each. I have an internal filter on each side of the tank. First is an aquaone 101f and the other is a fluval 2. I have carbon in the fluval 2. My fish seem OK, but I’m doing water changes every 2 days, I use the aqua safe for the tap water, and I’m using stress zyme, someone told me to get the temperature up to 78-80 Celsius to speed up the good bacteria growth. I’m just wondering if I should take 2 fish out and put them in my 35 liter tank that has been sitting fishless for 2 weeks with an internal filter on, maybe separating them will bring the ammonia down and then when it has finished cycling, I can add the fish back to the big one, because I plan to put tropical in to the 35 liter tank, but I want 2 get bused to using the heater on it. When I get my big one sorted then I do the tropical. But as far as the big tank goes I think I’m going to have to be patient and hope my fish don’t die. Any suggestions will be great! Thanks, kind regards.
Answer: What fish do you keep? Some species are hardier than others, so perhaps staying in the original tank won’t hurt them. 3 weeks isn’t that much to grow a good colony of nitrification bacteria. You can even buy nitrification bacteria at shops! I think that if they survived 3 weeks in there, it should be fine to house your fish in the same tank until everything gets more stable. Keep changing water, of course.
Al on May 30, 2010, 2:40 am wrote
I’m in the process of adding new salt water into a new tank. But before putting any fish / live rock... the water already has .25 ppm ammonia. Is that normal?
I’m in the process of adding new salt water into a new tank. But before putting any fish / live rock... the water already has .25 ppm ammonia. Is that normal?
Answer: It is not normal. You should perform the test once again to see if it wasn’t just a mistake caused by impurities. Otherwise you should cycle the tank.
weewee on July 7, 2010, 4:01 am wrote
It really depends on the fish too. Some fish are able to tolerate high levels. Even though if your water is at 0ppm all around, doesn’t mean that you got the healthiest fish.
It really depends on the fish too. Some fish are able to tolerate high levels. Even though if your water is at 0ppm all around, doesn’t mean that you got the healthiest fish.
nina on July 20, 2010, 4:14 pm wrote
Even after treatment with two different brands of betta water conditioner my tap water from a public source still has higher levels of nitrite (3.0 ppm) and nitrate (40 ppm) than my betta bowls which have 0 ppm nitrite and 20 ppm nitrate. This has been going on for the past month during the intense heat wave in the northeast. Is there any way to rectify this problem? It’s awfully expensive to use bottled water.
Even after treatment with two different brands of betta water conditioner my tap water from a public source still has higher levels of nitrite (3.0 ppm) and nitrate (40 ppm) than my betta bowls which have 0 ppm nitrite and 20 ppm nitrate. This has been going on for the past month during the intense heat wave in the northeast. Is there any way to rectify this problem? It’s awfully expensive to use bottled water.
Answer: Water conditioners will not remove nitrates and nitrites from the mains water, all conditioners do is lock ammonia and chlorine/chloramines. You say that the levels are fine once in the tank which proves that the filters in your tank are working efficiently so I don’t see what the problem is here. Regular water changes will keep the nitrates down and your filters will keep the nitrites at zero. [answered by Mick; fishtankforum.co.uk]
Brandi on July 26, 2010, 8:27 am wrote
I have a 100 gallon tank with a sump and three ten gallon tanks for that with lots of filters and bio balls. When I went away for two weeks I first tested my tank and it was fine, nothing out of the ordinary. Pretty much null across the board. We had someone watch the animals and feed the fish but when I came back my chocolate albino pleco and my turquoise discus had died and another pleco followed the next day so I tested my levels and they had skyrocketed! In two weeks my tank went from 0ppm ammonia to 8 and from 0 ppm nitrate to 40. The pH went from 7.2 to 6. The only one that stayed fairly normal was the nitrites at .25ppm. I am wondering what could have happened? I have never had a tank go south this fast on me. Especially when my 20 gallon that sits right next to it is fine. Neither tank is overstocked, if anything I have less than half the max amount. Any clues would be greatly appreciated.
I have a 100 gallon tank with a sump and three ten gallon tanks for that with lots of filters and bio balls. When I went away for two weeks I first tested my tank and it was fine, nothing out of the ordinary. Pretty much null across the board. We had someone watch the animals and feed the fish but when I came back my chocolate albino pleco and my turquoise discus had died and another pleco followed the next day so I tested my levels and they had skyrocketed! In two weeks my tank went from 0ppm ammonia to 8 and from 0 ppm nitrate to 40. The pH went from 7.2 to 6. The only one that stayed fairly normal was the nitrites at .25ppm. I am wondering what could have happened? I have never had a tank go south this fast on me. Especially when my 20 gallon that sits right next to it is fine. Neither tank is overstocked, if anything I have less than half the max amount. Any clues would be greatly appreciated.
Before you went away did you show your friend exactly how much food to give the fish? If the ammonia levels have risen sharply while you were away it sounds like excess food has been rotting in the tanks. The rise in ammonia will make your water more acidic thus reducing the pH drastically which can also be fatal to the fish if it happened too quickly. [answered by Mick; fishtankforum.co.uk]
steve on July 28, 2010, 11:57 am wrote
I have a 55 gallon saltwater tank; Live rock and sand, 2 clowns and a peppermint shrimp. pH is 8.3 and everything else is at zero. Local pet store said I could add fish but I don’t think my tank has cycled as I don’t remember any levels being high then low again. What should I do?
I have a 55 gallon saltwater tank; Live rock and sand, 2 clowns and a peppermint shrimp. pH is 8.3 and everything else is at zero. Local pet store said I could add fish but I don’t think my tank has cycled as I don’t remember any levels being high then low again. What should I do?
Answer: You can buy some hardy fish, or buy bacteria starter kits. Or simply wait a couple of days. However, if your peppermint shrimp lives normally in there, I wouldn’t mind adding new fish.
kerry on October 4, 2010, 9:58 am wrote
I have had a fish tank set up for bout 8 weeks. Now we have introduced fish weekly, they seemed fine for the first few weeks and over the past few days they have just stayed at the bottom of the tank long periods of time and they have also got white spot. We did a third water change and test the water. The pH levels are 7.6, the kh levels are 270, the gh levels are 50, the nitrite no3 levels are 50, the nitrite no2 levels are 5.0, and the ammonia levels are testing 1.0. Have you got any suggestions to make our fish feel better? Thank you
I have had a fish tank set up for bout 8 weeks. Now we have introduced fish weekly, they seemed fine for the first few weeks and over the past few days they have just stayed at the bottom of the tank long periods of time and they have also got white spot. We did a third water change and test the water. The pH levels are 7.6, the kh levels are 270, the gh levels are 50, the nitrite no3 levels are 50, the nitrite no2 levels are 5.0, and the ammonia levels are testing 1.0. Have you got any suggestions to make our fish feel better? Thank you
Answer: The readings for nitrites and ammonia should be 0 if the tank was cycled properly before you added any fish. The filters are struggling to cope with the amount of ammonia that the fish are producing and this is starting to affect the health of the fish. My advice would be to take half of the fish back to the store and let the filters catch up with the bio load. Once you start to get readings of 0 for your nitrates and ammonia you can add more fish but keep testing the water each time that you do so that you know your filter is coping. [answer by Mick; fishtankforum.co.uk]
elle on October 22, 2010, 10:43 am wrote
I have tested my aquarium and there is no ammonia present but nitrite at 1ppm... has anyone got any suggestions other than a water change to remove this? The aquarium setup is 500L, with goldfish (mainly small, but some large). There have been issues with nitrite in the past, but they have always been linked with high (or at least raised) ammonia and have been fixed by removing the ammonia and doing water changes. This time is more odd, because there isn’t any ammonia present. Reading the comments above, nitrite can usually be removed through proper filtration, so would you say we have a filter problem or is there something else?
I have tested my aquarium and there is no ammonia present but nitrite at 1ppm... has anyone got any suggestions other than a water change to remove this? The aquarium setup is 500L, with goldfish (mainly small, but some large). There have been issues with nitrite in the past, but they have always been linked with high (or at least raised) ammonia and have been fixed by removing the ammonia and doing water changes. This time is more odd, because there isn’t any ammonia present. Reading the comments above, nitrite can usually be removed through proper filtration, so would you say we have a filter problem or is there something else?
Answer: It’s already in the article The Essential Nitrogen Cycle: ...to convert ammonia into less toxic nitrites and then into even less harmful nitrates.... It simply means that the ammonia is decomposed fast, but then there’s a problem with process of decomposing nitrites to nitrates. So a small problem with filtration. You can buy products that support nitrites and nitrates decomposition, they have to be added into filtration chambers of a filter. In my experience these nitrite and nitrate removers are widely available on the market, so am not going to recommend any manufacturer.
mizz mae on November 13, 2010, 6:36 pm wrote
I’ve had my fresh water aquarium set up since October 15 and introduced 2 oscars on the 25th of October. My aquarium is a 29 gallon and eventually I’m going to get a much bigger tank as I know oscars need much more room. A few days after introducing my oscars both are about 2 inches long I started getting the ammonia readings. So I started to do partial water changes at first every day then every other day. 2 weeks in no changes on the ammonia levels and noticed my nitrites going up still been doing the partial water changes also noticed a few days later my nitrates were at 5.0ppm. So my ammonia has been steady between 1 and 2 ppm. Nitrites between 0.50 and 1ppm. pH 7.4. How can I be getting all three readings like this? I’m so confused about what’s going on. I don’t over feed them. They seem fine and healthy. From what I have been reading I should start to see the ammonia go down when the nitrites go up. I also used some stuff called cycle to help get the good bacteria going. I keep my tank between 78 and 79. So far it’s been 21 days that I’ve had the fish in the tank. Has anyone had this happen to them? Please help!
I’ve had my fresh water aquarium set up since October 15 and introduced 2 oscars on the 25th of October. My aquarium is a 29 gallon and eventually I’m going to get a much bigger tank as I know oscars need much more room. A few days after introducing my oscars both are about 2 inches long I started getting the ammonia readings. So I started to do partial water changes at first every day then every other day. 2 weeks in no changes on the ammonia levels and noticed my nitrites going up still been doing the partial water changes also noticed a few days later my nitrates were at 5.0ppm. So my ammonia has been steady between 1 and 2 ppm. Nitrites between 0.50 and 1ppm. pH 7.4. How can I be getting all three readings like this? I’m so confused about what’s going on. I don’t over feed them. They seem fine and healthy. From what I have been reading I should start to see the ammonia go down when the nitrites go up. I also used some stuff called cycle to help get the good bacteria going. I keep my tank between 78 and 79. So far it’s been 21 days that I’ve had the fish in the tank. Has anyone had this happen to them? Please help!
Answer by Mick; fishtankforum.co.uk: The Oscars have been added to the tank before the filters were cycled and they are now struggling to cope with the fish waste. Eventually the filters will catch up but in the meantime, your Oscars are living in water of a low quality so are prone to infections or disease until the filters catch up. Cycling the tank can take up to 4 weeks, if you can get hold of some media from a cycled filter and add it to yours it should help.
Raj on December 2, 2010, 4:05 am wrote
Hi. I recently got my tank up and running and started cycling with 4 bleeding eye tetras. Been monitoring the water regularly. At the moment the ammonia is 0-0.25 ppm and nitrite is at 1 ppm. I’ve heard a lot about nitrites also being toxic to the fish so was wondering what level I should try and keep the nitrites down to? I know I need nitrites to allow the bacteria to form but I don’t want too much in the tank that would be toxic to the fish! I’ve read that bleeding eyed tetras are pretty hardy? What levels should I try to maintain during the cycle so it’s not harmful to the fish? Thanks.
Hi. I recently got my tank up and running and started cycling with 4 bleeding eye tetras. Been monitoring the water regularly. At the moment the ammonia is 0-0.25 ppm and nitrite is at 1 ppm. I’ve heard a lot about nitrites also being toxic to the fish so was wondering what level I should try and keep the nitrites down to? I know I need nitrites to allow the bacteria to form but I don’t want too much in the tank that would be toxic to the fish! I’ve read that bleeding eyed tetras are pretty hardy? What levels should I try to maintain during the cycle so it’s not harmful to the fish? Thanks.
Answer: If there are fish in your tank, then minimum is recommended. Minimum of ammonia, minimum of nitrites. Nowadays many Tetra species are hardy due to historical reasons... they reproduce easily in captivity and thus it’s relatively easy to get a hardy fish after 100 or 200 generations.
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I have had my Marine Aquarium set up for 6 weeks and have 2 clown fish and 2 Damsel Humbugs, they seem healthy enough but the Ammonia level seems higher than one would expect, have done several 25% water changes over the last week and have installed a Polyfilter in my filter and added a polyfilter wedged between two rocks, the polyfilter has turned a yellowish green which according to the data that comes with the filter it is removing Ammonia, but a week on and a 25% water change the reading on the test kit is 1.2, has anyone got a suggestion, the water was tested by my local fish stockist who recorded an Ammonia level of 0.05, but my tests done with the Intrepid kit keeps showing higher levels.