Nitrate Problem

[JMcQueen]

Hi, Im having a bit of a problem with nitrates and was wondering if other members could help.

The problem is that Im constantly getting high nitrate level readings regardless of the water source. I tested the tank this morning for ammonia, nitrate and nitrate. The ammonia and nitrite are fine with negligible readings but nitrates showed heavily. Fair enough I though, I'll do a partial (10%) water change.

As a base level though, I tested the tap water for nitrate. It read high. Hmmm I thought, I then tested the water I had standing to reach room temperature (it had been treated). This also read high.

Therefore what do I do to get an accurate reading of whats actually in the tank when all water sources suggest high levels before they've even seen a fish!

 

[chrisbassist]

When you say high what do you mean? I have nitrate in my tap water. About .1

nitrate isn't as toxic as ammonia or nitrite, and there is no reason to get it to 0

 

[waterdrop]

Hi JMcQueen and Welcome to TFF!

Its not uncommon to have some Nitrate(NO3) in your tap water source. In most cases its not a bad problem. NO3 is tolerated in fairly high amounts by most fish, tests have shown no problems at 400ppm and even 1000ppm for some river catfish. In the typical community freshwater aquarium we like to strive for 15 to 20ppm -above- whatever the tap water NO3 level is as a max if we can help it but its not so critical. There are a few species exceptions like GBRs (German Blue Rams) that do better is very low NO3 levels.

In the freshwater aquarium, the goal for a fully working "biofilter" is to maintain Zero ppm ammonia and Zero ppm nitrite(NO2) and some steady level of Nitrate(NO3) as mentioned in the first paragraph.

In your post you mention small amounts of ammonia and nitrite(NO2) and this is a warning to us that you many need more information on the Nitrogen Cycle and the whole idea of cycling. Its just something we like to check on in case it can help a newcomer. What is your situation? How recently was the tank filled? What is the water volume? Are there any fish yet? Have you started cycling the filter by any method yet? What are your actual test results on your tap water? Exactly what make/model of test kit do you have?

We have excellent articles in our BRC (Beginners Resource Center) on the Nitrogen Cycle, the Fishless Cycle and the Fish-In Cycling Situation that can add to the things I'm discussing and may help you focus your questions. Anyway, hope we can help!

~~waterdrop~~

 

[JMcQueen]

Hi, Sorry for not getting back to you both sooner. I'll get the exact readings later on as Im at work at the moment.

Details of the setup is that its relatively small (about 30 litres) and is home to only the one fish. Unfortunately cycling without the fish wasnt an option as we needed a new home for him sharpish (the other developed a crack). In addition to the under gravel filter, theres also a mini fluval working as I know that generally, under gravel isnt very good. The kit Im using is a Tetrafin one.

I'll have a read of the beginers resources too. I was just confused as to how to get an accurate reading when it appears tape water is already quite higly loaded. Therefore how do I tell if whats in the tank is becoming a problem?

Oh, and in my hast for answers I've posted this in the wrong forum. Its actually a coldwater setup so please feel free to move.

 

[chrisbassist]

Cold water won't make much difference.

It has been shown that most fish can happily live in 400ppm of nitrate. While we wouldn't recommend this, and would say to keep it as low as possible, it shows how much is possible to have in the water.

Undergravel filters aren't bad, just people don't like them because your substrate gets dirty quickly and you have to put up with it, and when it comes to cleaning it it's a bit of a pain. But they're fine for doing the job.

 

[JMcQueen]

OK, I took some readings tonight before doing a 30% water change.

The water in the tank was Nitrite: 0.3 Ammoniua: 0.0 Nitrate between 50-110 (difficult to tell with the test tube colour)
The water going in to the tank(clean): Nitrite: 0.0 Ammonia: 0.0 Nitrate Between 20-50

 

[Assaye]

50-100 is actually fine. You want to keep it as low as possible but I believe it's been scientifically tested to show that seemingly high nitrate levels don't do damage to fish. Do some water changes to get your ammonia to zero though.

 

[JMcQueen]

Thats what I was thinking. Whats the minimum recommended change interval between water changes? I only tend to do 20-30% changes at most but dont want to do them too often to either over stress the poor chap or kill the bacteria I'm (hopefully) developing.

Depending on where you read, some people say do it every day until you can test for ammonia and nitrite to read zero. Others say do it every three days or so etc etc.

 

[waterdrop]

Thats what I was thinking. Whats the minimum recommended change interval between water changes? I only tend to do 20-30% changes at most but dont want to do them too often to either over stress the poor chap or kill the bacteria I'm (hopefully) developing.

Depending on where you read, some people say do it every day until you can test for ammonia and nitrite to read zero. Others say do it every three days or so etc etc.

This is incorrect information I believe. The presence of ammonia or nitrite(NO2) when fish are present is much more stressful and physically damaging than any sort of water change shock. (Water change shock is something we are at liberty to worry about when our biofilter is all established and working perfectly and we have zero ammonia and nitrite.) The bacteria will do fine even when the tests read zero ammonia because the tests aren't that sensitive. There is still plenty of ammonia exchange going on when an ammonia test reads zero ppm.

Your water changes are probably too small. You can change water more or less continuously and still be ok (always using good technique of course, dosing conditioner and roughly temperature matching) as far as the fish are concerned but in practice its usually good to wait at least an hour to allow a good followup test so you'll know what you accomplished with the last water change.

You mentioned that your last nitrite reading was .3ppm. That's about perfect as a maximum amount you want to see right before you change water again. Your goal is to be a bit of a detective and figure out what percentage and frequency of water changes will allow you to keep both ammonia and nitrite(NO2) below 0.25 or 0.30ppm (whatever your first testkit level is basically) before you can be home again to potentially change water again (most people test on about 12 hour intervals as they can handle things either in morning or evening.)

~~waterdrop~~

 

[JMcQueen]

Cheers Waterdrop, thats a great help.

I dosed another 30% of water last night after the water change so that I have some already at temperature should I need it tonight. I'll test the tank again tonight to see what the levels are.

 

[JMcQueen]

Bit of an update. Unfortunately, at some point during the day the fish died. The really concerning aspect is, im not sure why.

I left the house this morning and he seemed ok, he was chasing food etc and when I came home tonight he had died. I checked the water and ammonia was reading zero and nitrite about 0.1 and the temperature was spot on between new and tank.

The water has developed a heavy milky cloud though which I attribute to bacteria bloom? Could it be something else? Could it be that the bacteria has robbed the water of oxygen and thus suffocated the fish during the day?

I suppose the only postive that can be taken from this is that it allows the use of fishless cycle. Whats the best way of doing this? I dont want the same to happen again if we go out and buy another fish.

 

[waterdrop]

Yes, it could be the oxygen (a bacterial bloom can suck a huge amount of oxygen from the water) or it could simply be the stress of being in a cycling tank. Beginners who simply read the theory of fishless and fish-in tend to think of them as simply choices and don't remember the countless dead fish like a lot of us old guys do.

Ammonia, even in tiny amounts causes permanent damage to gill tissue, leading to shortened lives or death. Nitrite(NO2), even in tiny amounts, attaches to the hemoglobin protein on the fish red blood cell and does two things - it blocks the oxygen receptor and it causes a biochemical reaction that creates methemoglobin where the hemoglobin was, essentially oxidizing the red blood cell into a chocolate brown mush. This problem goes on no matter how tiny the nitrite amount is but we delineate "amounts" that are deemed "safe" simply because a fish is able to recover from the damage when its below a certain amount. By the time a biologist could see the brown blood, the brain and nerve tissue would already be damaged from lack of oxygen.

Its quite easy to switch over to a Fishless Cycle procedure, its simply good to find the right ammonia and get going quickly in hopes of salvaging some of the existing bacteria. The fishless writeup is in the BRC.

~~waterdrop~~

 

[drobbyb]

Yes, agree with everything waterdrop has said. Instead of leaving the tank empty, grab some household ammonia and continue the cycle. In no time (hopefully!) you will be able to restock the tank and get to the fun part of the hobby: keeping fish!

 

[OldMan47]

I will go much further than WD on the idea of water change stress. I will say, unequivocally, that a water change that is dictated by any other factor always takes precedence over any concern about the stress caused by that water change. I have been known to do a 90% + water change to correct a poorly cycled filter situation. When I test a newly established tank and find any ammonia or nitrites, I drain the tank to such a low level that the fish have trouble swimming at all. I then add back dechlorinated tap water to refill the system.; If I then test and find residual ammonia or nitrites, I will gladly repeat that huge water change. I find that such water changes are harmless and I do not lose fish as a result of such huge changes. What does that mean to me, water changes of any amount are not stressful enough to really bother the fish.

 

[JMcQueen]

I will go much further than WD on the idea of water change stress. I will say, unequivocally, that a water change that is dictated by any other factor always takes precedence over any concern about the stress caused by that water change. I have been known to do a 90% + water change to correct a poorly cycled filter situation. When I test a newly established tank and find any ammonia or nitrites, I drain the tank to such a low level that the fish have trouble swimming at all. I then add back dechlorinated tap water to refill the system.; If I then test and find residual ammonia or nitrites, I will gladly repeat that huge water change. I find that such water changes are harmless and I do not lose fish as a result of such huge changes. What does that mean to me, water changes of any amount are not stressful enough to really bother the fish.

Taking that on board, why do so many people go on about water change stress then? Also, what are the symptoms of a fish being stressed due to the water change alone. After I did the last large percentage water change, the fish went and hid at the back of the tank behind a plant and wasnt seen again alive. I matched the water temperatures to within a degree, dechlorinated the new water, syphoned it in and out so as not to cause huge currents from pouring water in etc.