What are the effects of High NITRATES on fish?

[Bubble_B0y]

when talking about water quality, we always discuss ammonia and nitrite.
But we often forget about nitrates -since they are relatively harmless at low levels.

So what are the actual effects of Nitrates on fish, at High levels?
Also, what is considered High nitrate level? above 40ppm?

 

[jcolon]

when talking about water quality, we always discuss ammonia and nitrite.
But we often forget about nitrates -since they are relatively harmless at low levels.

So what are the actual effects of Nitrates on fish, at High levels?
Also, what is considered High nitrate level? above 40ppm?

Below is from Fish Poop and You: A Primer - Aquarium Forum .... HOPE IT HELPS!

Nitrate is the least harmful of the three, but it can still have fatal consequences. 95% of the aquariums I test have at least a little bit of nitrates in them, and it's usually an unavoidable problem in most non-planted freshwater aquariums. While most people consider nitrate harmless except in larger quantities, the truth is that even in concentrations higher than 30ppm nitrate can cause an inhibition of growth and development, cause nervous system damage and degradation (through the inhibition of vitamin B12 uptake, a crucial part of proper nervous system function), and cause general overall stress for aquatic animals. Nitrate has secondary ramifications in that it can be used as a food for algae, which in epidemic proportions can cause major issues with water quality and chemistry. Algal blooms can also lead to water anoxia (a lack of oxygen in the water).

Unlike ammonia and nitrite, nitrate is not converted in most home freshwater aquarium systems into another substance. The most reliable (and easiest) way to lower nitrate levels in your aquarium is to do a simple water change. Chemical filtration methods are available to strip nitrates from the water, but these don't revitalize the ion balance of the water like a water change will.

Symptoms of nitrate poisoning

Nitrate poisoning is a little sneakier than ammonia or nitrite poisoning, as outward symptoms may not present themselves until the latter stages of the poisoning process. General listlessness, lack of feeding reflex, erratic swimming and behaviors, and overall poor health are all signs of nitrate poisoning; generally if these are noticed, your fish has suffered at least a little permanent damage. Your only recourse is to quickly rectify the nitrate issue and hope for the best.

Here's the good news: unless you are cycling a new tank, you won't generally see the first two unless something drastic has gone wrong with your aquarium. Having a good set of test kits on hand capable of testing these three compounds (in addition to pH, hardness, and alkalinity) is never a bad idea, and a water test should always be your first course of action when presented with an unknown problem. Having accurate numbers to present to us here also helps us help you. Learn the nitrogen cycle, learn how to properly maintain your tank, and with any luck The Big Three should never rear their ugly heads past the cycle process.

 

[BBradbury]

Nitrates

Good morning Bubble...

If you remove half the water in your tank weekly, you won't have to worry about nitrate levels.

I change half the water in my tanks every week and have strong filtration and haven't tested the water in a couple of years.

Not saying this will work for you, but I've found over the years that if you follow a sound tank maintenance schedule, you won't need a water testing kit. I haven't used mine in quite a while.

B

 

[aqua_chem]

The thing about nitrates is that they tend to correlate with other things that you cant measure, like dissolved organics. So while nitrate being high might not ne a huge issue, it generally means that you haven't been as diligent with water changes and organics are up too.

 

[Fishguy2727]

Ditto with aqua chem.

Nitrate itself is not a major issue in most cases. But as stated, it correlates very well with all the other things that do build up that we don't have test kits for. Many fish give off growth inhibiting hormones that stunt growth. Dissolved organic compounds also build up. Fortunately these are low if nitrate is low (unless the tank is planted). You can also test the TDS to monitor water quality. You can watch it go up with times as all these things build up. There can be a lot of error if you add any aquarium salt (which shouldn't be done all the time in a freshwater tank). You also need to compare it to your tap water so you know what your starting point is. If the fish get sick or stressed and you add salt you just need to test before and after so you know how much it alone brought the TDS up. The good thing is that a TDS meter takes only a couple seconds and costs about $10 shipped on eBay.

In a planted tank the nitrate can be actively reduced by the plants. This means that the nitrate will be low even if all the other things are not. This is why it is important to keep up a good water change schedule in a planted tank, even if the nitrate is low.

 

[aqua_chem]

Ditto with aqua chem.

Nitrate itself is not a major issue in most cases. But as stated, it correlates very well with all the other things that do build up that we don't have test kits for. Many fish give off growth inhibiting hormones that stunt growth. Dissolved organic compounds also build up. Fortunately these are low if nitrate is low (unless the tank is planted). You can also test the TDS to monitor water quality. You can watch it go up with times as all these things build up. There can be a lot of error if you add any aquarium salt (which shouldn't be done all the time in a freshwater tank). You also need to compare it to your tap water so you know what your starting point is. If the fish get sick or stressed and you add salt you just need to test before and after so you know how much it alone brought the TDS up. The good thing is that a TDS meter takes only a couple seconds and costs about $10 shipped on eBay.

In a planted tank the nitrate can be actively reduced by the plants. This means that the nitrate will be low even if all the other things are not. This is why it is important to keep up a good water change schedule in a planted tank, even if the nitrate is low.

Plants also help with some organics, mostly organic waste products. They do very little for secreted compounds (hormones and such).