How should i test Nitrates

Most countries have maximum allowed levels of nitrate but they don't all use the same unit of measurement.

The UK and our test kits use the nitrate-NO3 scale and the UK allows up to 50 ppm nitrate in drinking water.
The US allows 10 ppm on the nitrate-N scale.

The conversion factor is 1 ppm nitrate-N = 4.427 ppm nitrate-NO3.
So the US limit of 10 ppm nitrate-N is the same as 44.27 nitrate-NO3, slightly less than the maximum allowed by the UK. I suspect both countries went for round numbers.
Thank you Essjay, so not quite as bad as i thought then (not great) but not as bad.

The problem i have is, how do I accurately test my nitrates? Im measuring 0 Ammonia, 0 Nitites yet unable to get a workable reading for Nitrates (which was going to be my guide for water changes) etc
 
As the others have said, with liquid testers one of the bottles should be shaken very well. it's bottle #2 with the API tester. These bottles contain a reagent that isn't really soluble so it settles out on the bottom of the bottle and the bottle has to be shaken to get it back in to the liquid. If the bottle hasn't been moved for a while it can form a solid lump. That's why you'll read to bang it on the worktop a few times before shaking, to break up any lumps.
The instructions will say how long to shake the bottle, most people do it for longer. Then once the drops are added to the test tube, the tube has to be shaken for the length of time it says and then the time measured.

Very silly question - you are using both bottles for ammonia and both bottles for nitrate? We once had a member who thought that the bottle #2's were spares for when bottle #1 ran out.



Nitrates shouldn't be used to guide water changes - most of us change 50% or more once a week. If you have plants they will distort things as they take up the ammonia made by the fish and they don't turn it into nitrite or nitrate, so a heavily planted tank can have zero nitrate even right before a water change.
 
As the others have said, with liquid testers one of the bottles should be shaken very well. it's bottle #2 with the API tester. These bottles contain a reagent that isn't really soluble so it settles out on the bottom of the bottle and the bottle has to be shaken to get it back in to the liquid. If the bottle hasn't been moved for a while it can form a solid lump. That's why you'll read to bang it on the worktop a few times before shaking, to break up any lumps.
The instructions will say how long to shake the bottle, most people do it for longer. Then once the drops are added to the test tube, the tube has to be shaken for the length of time it says and then the time measured.

Very silly question - you are using both bottles for ammonia and both bottles for nitrate? We once had a member who thought that the bottle #2's were spares for when bottle #1 ran out.



Nitrates shouldn't be used to guide water changes - most of us change 50% or more once a week. If you have plants they will distort things as they take up the ammonia made by the fish and they don't turn it into nitrite or nitrate, so a heavily planted tank can have zero nitrate even right before a water change.
Hiya Essjay, yes im doing everything to the Book, i searched this Forum and read all about the Nitrates Bottle two needing a good beating as it solidifies. I will try and double the shake time but TBH i shook til my head nearly fell off.

I do have wuite a lot of plants in the tank and they have started growth.

The tank was fully cycled using Dr Tims prior
 
An observation or two that may help at least in understanding if not solving. First, @Essjay explained the two different scales used, one by the hobby and the other by water authorities, and how to convert. So go with your API test for both tank and tap (inconsistency will occur otherwise) and just be aware of the different values for tap water. Shake the Regent #2 for a good two minutes, including some thumping, and there is no reason to doubt the results.

Second issue concerns plants. Aquatic plants, growing submersed or floating, will keep nitrates that occur within the biological system low. This is because most aquatic plants take up ammonia/ammonium as their nitrogen, and this means with sufficient plants that are fast growing (floating plants are ideal here) the ammonia produced by fish will largely be taken up by these plants. Nitrite does not result as it would if the bacteria/archaea are using the ammonia/ammonium, and thus nitrate is not produced at the next stage. Some ammonia will get taken up by the nitrifiers but very minimal with sufficient plants.

However, this is not the case with nitrate occurring in the source water. Aquatic plants will not take upnitrate unless they are forced to, which means they have insufficient ammonia/ammonium in balance with the other nutrients and light. Aquatic plant uptake of nitrate is more prevalent in heavily-planted tanks using what we term a high-tech method, with brighter light and more frequent dosing of all nutrients including diffused CO2. For those of us with low-tech or natural planted tanks, there will almost always be sufficient ammonia/ammonium for the needs of the plants. The can and do (if available) take up more than they actually need, which is why good floating plants are often referred to as "ammonia sinks." Quite a benefit.

Nitrates occurring from the biological system are thus much easier to eliminate (or prevent more accurately). Those occurring in the source water should be dealt with before they enter the aquarium, depending upon the level. One of our members @AbbeysDad has dealt with this issue for many years and has some good information. [Lost my bookmarks recently, but he will see this thread and post I'm sure.]

You want nitrate as low as possible as they do impact fish, slowly but significantly for some species. Water changes help maintain stability, and the nitrate should always be the same from change to change.
 
An observation or two that may help at least in understanding if not solving. First, @Essjay explained the two different scales used, one by the hobby and the other by water authorities, and how to convert. So go with your API test for both tank and tap (inconsistency will occur otherwise) and just be aware of the different values for tap water. Shake the Regent #2 for a good two minutes, including some thumping, and there is no reason to doubt the results.

Second issue concerns plants. Aquatic plants, growing submersed or floating, will keep nitrates that occur within the biological system low. This is because most aquatic plants take up ammonia/ammonium as their nitrogen, and this means with sufficient plants that are fast growing (floating plants are ideal here) the ammonia produced by fish will largely be taken up by these plants. Nitrite does not result as it would if the bacteria/archaea are using the ammonia/ammonium, and thus nitrate is not produced at the next stage. Some ammonia will get taken up by the nitrifiers but very minimal with sufficient plants.

However, this is not the case with nitrate occurring in the source water. Aquatic plants will not take upnitrate unless they are forced to, which means they have insufficient ammonia/ammonium in balance with the other nutrients and light. Aquatic plant uptake of nitrate is more prevalent in heavily-planted tanks using what we term a high-tech method, with brighter light and more frequent dosing of all nutrients including diffused CO2. For those of us with low-tech or natural planted tanks, there will almost always be sufficient ammonia/ammonium for the needs of the plants. The can and do (if available) take up more than they actually need, which is why good floating plants are often referred to as "ammonia sinks." Quite a benefit.

Nitrates occurring from the biological system are thus much easier to eliminate (or prevent more accurately). Those occurring in the source water should be dealt with before they enter the aquarium, depending upon the level. One of our members @AbbeysDad has dealt with this issue for many years and has some good information. [Lost my bookmarks recently, but he will see this thread and post I'm sure.]

You want nitrate as low as possible as they do impact fish, slowly but significantly for some species. Water changes help maintain stability, and the nitrate should always be the same from change to change.
Thanks for all the feedback guys, i do appreciate it. Im looking at some seachem denitrate at he moment, maybe this could go into my cannister filter?
 
@Byron Can you comment on Riperian plants WRT the above and if they will take up nitrate?

If by riparian plants you mean terrestrial plants with their roots in the aquarium water but not their leaves and stems, yes, these remove nitrates. Terrestrial plants use nitrate as their preferred source of nitrogen and if the roots are in the aquarium water they will take up nitrates from the water. They primarily (maybe exclusively, doesn't matter) take up nitrate via their roots, unlike aquatic plants which take up ammonia/ammonium via the leaves.
 
Yes, Pothos and Bamboo in my case, and thanks!

You do have to be careful as some of these terrestrial plants have toxic saps. Pothos is one, and Philodendron comes to mind too. I realize there are some sources online that say Pothos is safe, but there are others the opposite, and I would not risk my fish. Bamboo I believe is safe, unless someone else corrects this thinking.
 
You do have to be careful as some of these terrestrial plants have toxic saps. Pothos is one, and Philodendron comes to mind too. I realize there are some sources online that say Pothos is safe, but there are others the opposite, and I would not risk my fish. Bamboo I believe is safe, unless someone else corrects this thinking.
Thanks, I recall reading that, along with some discussion as to the pH WRT dissolving the crystals (IIRC). My stock pretty much ignores the roots after a quick look see if I add new plants.
 
I recommend the Salifert test kit for nitates. Much easier to use and can test from .2 to 100 parts nitrates. But as with all test kits, you should view under bright white lighting. I use it and prefer it over api’s test kit for nitrates.
https://www.amazon.com/dp/B001EHCDBW/?tag=ff0d01-20
If you get it, I recommend laminating the test card to prevent water damage.
 
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If you are using a liquid API test kit please make sure that you are vigorously shaking the solutions for more than the minimum time stated in the instructions. This is VERY important to the accuracy of the test. If you are using teast strips quit doing so as they are not accurate.
 
I recommend the Salifert test kit for nitates. Much easier to use and can test from .2 to 100 parts nitrates. But as with all test kits, you should view under bright white lighting. I use it and prefer it over api’s test kit for nitrates.
https://www.amazon.com/dp/B001EHCDBW/?tag=ff0d01-20
If you get it, I recommend laminating the test card to prevent water damage.
That was the second kit i purchased.
 

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