How should i test Nitrates

[itiwhetu]

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.

You are correct, but if you have an understocked tank then the nitrates will be used by the plants won't they

 

[Fishmanic]

That was the second kit i purchased.

and how did you like the Salifert nitrate test kit compared to the API nitrate test kit

 

[The Dog]

and how did you like the Salifert nitrate test kit compared to the API nitrate test kit

Hiya Fishmanic, well it was certainly a lot easier to use than the API kit. If i had a choice it would be Salifert all the way. But neither match what South Staffs are claiming so still not happy. Maybe i will need to send a sample to an independent lab.

 

[Oblio]

Hiya Fishmanic, well it was certainly a lot easier to use than the API kit. If i had a choice it would be Salifert all the way. But neither match what South Staffs are claiming so still not happy. Maybe i will need to send a sample to an independent lab.

There seems to be some debate/uncertainty in the questions/comments on Amazon if this works for freshwater, or possibly the color chart is for saltwater only. Can you advise?

 

[Byron]

You are correct, but if you have an understocked tank then the nitrates will be used by the plants won't they

It depends upon the whole picture. Most aquatic plants will only take up nitrate if ammonia/ammonium is lacking and depending upon the balance (lighting and 17 nutrients). In order to use nitrate, most aquatic plants have to use considerable energy to change nitrate back into ammonium, so this is something of a last resort and usually occurs in high-tech systems.

 

[Byron]

You are correct, but if you have an understocked tank then the nitrates will be used by the plants won't they

It depends upon the specifics. Everything else has to be available before plants will waste energy converting nitrate to ammonium in order to use it.

 

[The Dog]

There seems to be some debate/uncertainty in the questions/comments on Amazon if this works for freshwater, or possibly the color chart is for saltwater only. Can you advise?

Ive no idea, the colour chart goes upto 100ppm if that helps

 

[TwoTankAmin]

There is a piece of this puzzle which is being missed. When it comes to municipal water supplies these normally end at the property line. So, the water company workis to minimize nitrification withing their system. However, when iy hits your home, reseidential complex or apartment building, what happens is of no concern to the water company.And what does happen there?

Almost all homes and apartment buildings have parts of their plumbing that are not very active. This might be a basement sink or bathroom, a guest bathroom rarely used etc. In the pipes around such "somewhat dead spots" nitrifying bacteria tend to accumulate. If you have a water co. that uses chloramine especially, the bacteria in these spots are not killed by chloramine or even very low levels of chlorine. When there is any ammonia present, the bacteria will thrive, And when they do, the end result is, you guessed it, nitrate.

So without realizing it, out own plumbing may be responsible tor seeing some of the nitrate in our tap. If the water company is also allowing a small amount of it through their pipes and then it combines with some being made in our pipes, we see elevated nitrat on our tap.

One subject in relation to the bacteria and the biofilms in which they live that we rarely hear discussed in the hobby is something called shear force. This relates the the strength of the water flow reaching a point where it can dislodge bits or even all of the biofilm from a hard surface. In the places where we run water every day it is not as easy for the bacteria to establish. But in the "dead" areas of the plumbing, places where the tap is rarely turned on and/or a toilet is not flushed somewhat regualrly, the bacteria have a much better chance to make a home for themselves.

I stumbled onto the plumbing info when I found it in the Ph.D. thesis of a microbilogist. This was later tidied up a bit and became published research in a scientific journal.

 

[AbbeysDad]

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?

It might seem like Seachem Matrix and/or De*Nitrate can solve all your nitrate woes, but in my long term testing using these products, I was never able to see any noticeable reduction in tank nitrates. I suppose it could happen, just never did for me!
Lots of plants to convert ammonia into plant tissue (later removed by trimmings), and deep sand can help. Also, I've had success with API NitraZorb, a rechargeable resin that traps nitrates and can be recharged with ordinary salt water.
Aslo see:
Filtration and Water Quality