Thats just wrong gilly, sorry. Nitrate is still toxic, it just takes higher amounts and over 50ppm is enough to stress, cause illnesses (by suppressing the immune system), stunt growth and will kill new additions like low amounts of ammonia and nitrite would. If your source tap water contains high amounts of nitrate then either use store bought re-mineralised RO or install an RO filter at home and re-mineralise it yourself.
Your current Fish tank Setups!
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Caporegime
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My vet disagrees with you. That's where I got the advice.
Tap water nitrates are not something to worry about 99% of the time. The reason people worry about elevated nitrate levels is because they are the 'smoking gun' that points to ammonia and nitrites having been present previously.
Sorry but unless he's an aquatic specialist thats like saying a dentist can give specialist advice about sore knees - vets don't get training in aquaculture unless they choose it as a speciality. Same as RSPCA officers and sadly why so many fish end up dead due to the perceived authority of the knowledge these people dispense. Either way he's still wrong - 50ppm would be on the threshold for toxic to animals too hence why its the most you're allowed in drinking water.
@king - Nitrate will always be present in your tank water at higher levels than your source water with a fully cycled biological filter, unless you are running a very low nutrient reef and then nitrogenous waste should be almost undetectable.
@ Mike - Setting up RO isn't cheap, something like this is a very basic unit which you need to buy extra stuff to plumb it into the mains, if your pressure is too low then you'll need pumps to make the systems work, storage space to hold it while you make it suitable for fish, re-mineralising salts etc and for most people its just not worth it unless you're into marines, asian or wild discus and other fish that like really soft water. That place does other RO units and equipment so you can look around for ideas, but with your source nitrate I'd just buy some re-min'd RO from my local store and dilute the tap water if it got to be a problem.
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Caporegime
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He is an aquatic specialist. I wouldn't refer my fish to someone who wasn't.
His advice, and I quote -
It is interesting that advice on the 'internet' quite often contradicts the advice by vets. For example, I have had the following two issues:-
Bloating and raised scales. The internet said it's dropsy, and incurable. The vet said it's most likely to be a heart valve infection, which recovered successfully following treatment.
Pop Eye. The internet said treat with a broad scale antibiotic. It turned out that there was a water contamination issue (I was away for a couple of days and left my daughter in charge). The swollen eyes reduced following a 50% water change, within a day.
Soldato
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I would show you my uni fish, but the set up is somewhat disappointing haha
Caporegime
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You are right, according to that he is a fish vet. I don't agree with him because he is wrong and know if I put my fish in your water they would most likely die.
<edit>This is an article on what most in the trade would advise regards nitrates. I know who I trust more </edit>
<edit>This is an article on what most in the trade would advise regards nitrates. I know who I trust more </edit>
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Caporegime
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I genuinely don't know how to respond to that. My fish are fine, why wouldn't yours be?
Monkeh said:
Or if you have a healthy planted tank
Any article that begins with an assertion that nitrates cause algae is to be taken with a large mountain of salt.
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Or if you have a healthy planted tank
Any article that begins with an assertion that nitrates cause algae is to be taken with a large mountain of salt.
Encourage != cause therefore they advise right and tbh if you don't get the correct balance of nutrients, CO2 and light to grow plants or even enough plants, algae will grow and use up the nitrates. But planted tanks are another area altogether and most systems you'd need to be adding an extra source of nitrogenous waste because plants can strip it from the water as ammonia faster than the bio filter converts it up the chain.
@Gilly - There are conflicting studies on the subject but recent ones suggest nitrate toxicity to behave like this. From personal experience of diagnosing customer fish deaths working in the trade its a pretty common event for people with established tanks and their regular weekly or fortnightly 1/4 water change where they never check nitrate to lose some guppies or tetras to old age, come buy fish and they get sick or die within a week. You go through a water check and the only thing you find wrong is nitrate >100ppm, you work with them to lower it back down again and when they put the new fish in again they thrive.
Reasonable deduction suggests to me that nitrate if not outright toxic is enough of an irritant to stress fish not used to it - but over time if the levels have increased slowly some fish will acclimatise to it, others start getting ill very quickly - guppies, mollies and neons from the bread and butter stuff spring to mind. So yes I will disagree with a vet who seems to be basing his advice from books and not practical experience.
End of the day I'm not just trying to argue on t'net - I enjoy keeping fish and believe the best way to do it is in clean water. I'm about to set up a 5x2x2 for discus and if my tap water wasn't good enough to get away with the HMA filter I'm using then I'd be getting an RO in for the 50% (300l+) water changes they'll need every day to begin with. But thats my choice, I could get a couple of Oscars and a plec and do the 25% a week they'd need instead.
It's difficult to have an informed discussion about something like nitrate toxicity in aquaria because there's so little appropriate data out there.
There are a handful of relatively long-term studies measuring "no effect observed concentration" (NOEC) levels of nitrate on fish, but they tend to focus on species that are known to be particularly sensitive (salmonids), and in particular on eggs and fry, none of which is terribly applicable to whats going on in our tanks. I had a look recently and found two studies for juvenile freshwater non-salmonids, which gave 30 day NOECs of 490 and 580 ppm, and precisely one study on adult freshwater non-salmonids, which gave an NOEC of ~1400ppm, but over only 9 days I think, so again fairly useless.
There are a number of other studies out there, but they all measure LC50 (concentration required to kill half the population in a given time), which I think we'll all agree is a pretty terrible measure from an aquarist's point of view
One interesting observation was that for a given species, nitrate toxicity increases significantly in soft water compared to hard water, so RO may have it's cons as well as pros if not paired with an appropriately rigorous water change regime (just a thought, not trying to be difficult).
Then of course there's the issue that hobbyist test kits are completely useless and inaccurate.
There are a handful of relatively long-term studies measuring "no effect observed concentration" (NOEC) levels of nitrate on fish, but they tend to focus on species that are known to be particularly sensitive (salmonids), and in particular on eggs and fry, none of which is terribly applicable to whats going on in our tanks. I had a look recently and found two studies for juvenile freshwater non-salmonids, which gave 30 day NOECs of 490 and 580 ppm, and precisely one study on adult freshwater non-salmonids, which gave an NOEC of ~1400ppm, but over only 9 days I think, so again fairly useless.
There are a number of other studies out there, but they all measure LC50 (concentration required to kill half the population in a given time), which I think we'll all agree is a pretty terrible measure from an aquarist's point of view
One interesting observation was that for a given species, nitrate toxicity increases significantly in soft water compared to hard water, so RO may have it's cons as well as pros if not paired with an appropriately rigorous water change regime (just a thought, not trying to be difficult).
Then of course there's the issue that hobbyist test kits are completely useless and inaccurate.
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Caporegime
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Thanks for linking to the article Monkeh. I do appreciate that I wouldn't want sustained high levels of nitrate but as I do a weekly 25% water change and my tank is heavily planted, I have relatively little to be concerned about.
I agree with you that just because he's a vet doesn't necessarily make him right. He has formed an opinion based upon research and observation, which may be limited in scope.
What I do strongly object to is following 'internet advice' without doing further research. There are so many forums that recommend chucking chemical after chemical into the water, when 99% of the time the fish just need a correct environment to recover and thrive, something which you have pointed out.
I agree with you that just because he's a vet doesn't necessarily make him right. He has formed an opinion based upon research and observation, which may be limited in scope.
What I do strongly object to is following 'internet advice' without doing further research. There are so many forums that recommend chucking chemical after chemical into the water, when 99% of the time the fish just need a correct environment to recover and thrive, something which you have pointed out.
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Sorry for going back over a little on the posts that led to here, Mike had some guppies that fell ill, I understand he shops here. This place is a great store, and one I buy from too via mail order. If you go to their mail order page they have a box on the left headed Before Arrival, yes the websites not great but they're fish keepers not web designers - it says:
As you can see from the bit in bold they also advise low nitrates in your tank. They also have narrower parameters than I quoted to Mike which are what I'd call normal for most tropical community fish.
To be honest the whole issue around nitrates when you work in the trade feels like an outlier at first, but over time you see it as a regular enough occurrence so that its the first thing you check once you've asked how long has the tank been set up and what sort of water change routine you have. Weirdly its not really something covered in literature and it might not even be the nitrate itself, I've seen discussions about whether its something we can't test for at home like other dissolved organic compounds which would also be reduced in concentration by dilution with fresh water change. Either way if your fish are off colour you could do a lot worse than giving them some clean water.
@Gilly - agree completely about throwing meds into a tank, and to be honest I've known a lot of stores to be quick to sell remedies on the back of problems just to boost sales rather than work to solve the problem. I still would feel uneasy having water with nitrates as high as yours, have you had your water checked in a store to see if your kit hasn't gone funny?
As you can see from the bit in bold they also advise low nitrates in your tank. They also have narrower parameters than I quoted to Mike which are what I'd call normal for most tropical community fish.
To be honest the whole issue around nitrates when you work in the trade feels like an outlier at first, but over time you see it as a regular enough occurrence so that its the first thing you check once you've asked how long has the tank been set up and what sort of water change routine you have. Weirdly its not really something covered in literature and it might not even be the nitrate itself, I've seen discussions about whether its something we can't test for at home like other dissolved organic compounds which would also be reduced in concentration by dilution with fresh water change. Either way if your fish are off colour you could do a lot worse than giving them some clean water.
@Gilly - agree completely about throwing meds into a tank, and to be honest I've known a lot of stores to be quick to sell remedies on the back of problems just to boost sales rather than work to solve the problem. I still would feel uneasy having water with nitrates as high as yours, have you had your water checked in a store to see if your kit hasn't gone funny?
It's more likely, in my opinion, that high nitrates are correlated with high BOD (biological oxygen demand) through overfeeding, over stocking or poor maintenance, which causes CO2-induced respiratory stress in fish through the Bohr effect as a result of the nitrifying bacteria stripping large amounts of oxygen from the water in order to process all that ammonia and nitrite. Or even that polluted water reduces the steepness of the diffusion gradient for ammonia between the fish's bloodstream and the water column and ammonia is therefore expelled more slowly, causing damage over time.
I'm in no way disagreeing that having greatly increased nitrates compared to your tap water is probably a bad sign, or that water changes aren't almost always a good thing, but the toxicity of the nitrate ion itself is unlikely to be the major issue. As I said, it's a smoking gun. Seeing as anecdotal evidence is all we have to go on, one of the planted aquarium 'gurus' in the US ran a small experiment where he dosed nitrates to a steady 160ppm for three weeks and saw no detrimental effects on his fish, including (if I remember correctly) a breeding group of Sturisoma. Still not exactly rigorous, but it works as a demonstration.
And as I mentioned previously, getting accurate and repeatable measurements of nitrate at home is nigh on impossible. Or, for that matter, in a lab - I know a guy who works as a water quality scientist with access to thousands of pounds worth of lab equipment and he can't manage meaningful nitrate readings with all that, which is why most water pollution studies now measure BOD if possible (still too difficult for most labs) or fluorescence analysis of tryptophan as a measure for levels of dissolved organic matter.
Which is why I always say everyone should have plants in their tank (especially floaters or emergents with access to atmospheric CO2), because then you can completely forget about the entire issue and be sure that your water quality is probably OK because the plants are actively capturing and exporting nitrogenous compounds, heavy metals and all kinds of other crap.
I'm in no way disagreeing that having greatly increased nitrates compared to your tap water is probably a bad sign, or that water changes aren't almost always a good thing, but the toxicity of the nitrate ion itself is unlikely to be the major issue. As I said, it's a smoking gun. Seeing as anecdotal evidence is all we have to go on, one of the planted aquarium 'gurus' in the US ran a small experiment where he dosed nitrates to a steady 160ppm for three weeks and saw no detrimental effects on his fish, including (if I remember correctly) a breeding group of Sturisoma. Still not exactly rigorous, but it works as a demonstration.
And as I mentioned previously, getting accurate and repeatable measurements of nitrate at home is nigh on impossible. Or, for that matter, in a lab - I know a guy who works as a water quality scientist with access to thousands of pounds worth of lab equipment and he can't manage meaningful nitrate readings with all that, which is why most water pollution studies now measure BOD if possible (still too difficult for most labs) or fluorescence analysis of tryptophan as a measure for levels of dissolved organic matter.
Which is why I always say everyone should have plants in their tank (especially floaters or emergents with access to atmospheric CO2), because then you can completely forget about the entire issue and be sure that your water quality is probably OK because the plants are actively capturing and exporting nitrogenous compounds, heavy metals and all kinds of other crap.
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