Nitrite levels and where they should be

Nitrate may be the least researched of the three forms of nitrogen we deal with in the cycling process. It is the least harmful of the three, but is still not good for fish. What are considered acceptable levels have been declining since I entered the hobby . To some extant there is no universal number because each species can be different in what level the can tolerate.

So, the easiest thing to do is target a maximum reading of about 20 ppm. The biggest risk I heave seen in the research is that elevated nitrate can interfere with reproduction in some fish. What it boils down to with nitrate is lower is always better. I would not want to see it hit 40 ppm in any of my tanks. Very high nitrate harms fish in much the same way as nitrite can. It just takes higher concentrations to do similar harm.

That said, I cannot recall the last time I tested my tanks (except the one with the continuous monitor). When I cycle a new tank or restart the bio-farm, I only test for ammonia because I seed bacteria and that means there is almost always a proper balance between the ammonia and nitrite bacteria at the start. I have replaced several nitrate test kits over the years because they expired unopened. One reason I do not need to test is I am very good about changing over 50% of the water in my tanks weekly. Over 20 years or about 1,040 weeks I have missed maybe 50 weeks. Most due to illness and a few due to being away from home.

As you keep fish and tanks over time, you should begin to develop a second sense that alerts you when something is off in a tank or with a given fish. I find I can watch a tank for a bit and I will see anything in the fish behavior that is odd. Just like you knew your fish had a clamped gill and that meant something was wrong, we notice things like that unconsciously.

Once I we know something is wrong, we look to discover why. This might be the only time I ever test water. However, after my very first tank I have never had any cycling issues. This is another reason my testing has dropped to almost nothing. However, tap water parameters, even from a private well, can change over time. So it pays to check every now and then. Because of my tank with the monitor and having to premix. I have a good feel for tap parameters weekly.
 
It is easier for me to see it in the steps. I am rounding up or down a tiny bit along the way.

Nitrite - 3 ppm x 10 = 30 mg/litre needed

1. 37 gal tank x .85 = 31.45 gals.
2. 31.45 gals x 3.75 = 117.94 litres.
3. 30 mg/l x 117.94 litres = 3,538 mg of chloride needed.
4. 3,538 mg x 1.5 salt factor = 5,307 mg of salt.
5. 5,307 mg/1000 = 5.31 gm of salt to be added.

1/4 teaspoon = 2 gm.
5.31 gm needed/2 gm = 2.65 x .25 teaspoons = .663 teaspoon. So you were fairly close, unless my math is off.

It is not easy to work in 1/3 teaspoon increments and you need 2/3 of a teaspoon. Like I said. it doesn't take lots of salt and most fish will not care about this amount. If you have both a 1/2 and a 1/8 teaspoon in your set, adding one level spoon of each will result in .5 + .125 = .625 teaspoons. this is pretty close to the desired .663. It is only 6% less and that would mean it produces about 28.2 ppm. Use your judgement. I do not think it matters if one is +/- 6% on the chloride, especially since some would suggest less than I do.

Please understand the salt will block the nitrite but it will still be in the water. The tank is safe when you can read 0 nitrite and not before.

If you want to take things down to the most accurate, i would tell you that you can also remove some of the salt as the nitrite readings drop. But it means more math. If your nitrite drops to 2 ppm you can change 1/3 of the water and that removes 1/3 of the salt. It is important that should nitrite levels rise, you add the proportionate amount of more salt. You are working towards desired concentrations.

To those reading here there is another way to do this all but it takes a sw fish keeper who can measure salinity. They know how much salt to add to a tank because they measure it with an hydrometer or a refractometer. And then you need the formu;las for converting wmy stuff to salt stuff. i have no experience in sw keeping, hence I do the above.

What FF suggest would help, but it will also slow the cycle. It will convert the ammonia in the tank to a form the ammonia bacteria do not use as effectively. So nitrite production is slower and thus fixing it slows as well. I would suggest this for an ammonia issue since we cannot neutralize it by simpler means than detoxifying it chemically. However, that also makes testing for ammonia to go wonky. I do not know how it might change nitrite test results. This is all they state about Prime and nitrite (which you must overdose for this).


This is not the science I prefer to see. They do not even consider that the prime may effect the test results as they know it does for ammonia testing.

If you can borrow bacteria that would also help. However, there is no way to know what else might come in with things from the tanks which are not under your control. I prefer to see this done form a person's other tanks if they have them. Otherwise one risks bringing in something unwanted with donated bacteria. Again, I think this is more useful when there is also an ammonia issue. You can solve your nitrite problem with a bit of salt. I cannot imagine anything easier.

and I used nitrate not nitrite in the calculation.

Nitrite is 20 x10 = 200

(200 x 37g x .85 x 3.875l/g x 1.5) 1000 = 36.5g / 8 g/tsp = 4.5 tsp.
 
G goldfish123457 , I think you are mixing up your readings for nitrite and nitrate.
 
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To throw this in the air, after cycling a fish tank the water changes you should is not according to nitrate tests. After cycling, you should always do weekly water changes of 50% but more (thinking 80%) because you got a goldfish in such small tank.
Goldfishes get very large and are very messy fishes so after cycling you may need to do twice or three 80%, maybe more, water changes per week.
What kind of goldie you got? Even fancies tend to outgrow regular aquaria, IMO goldfishes are way more suitable for outdoor ponds.


G goldfish123457 , I think you are mixing up your readings for nitrite and nitrate.
true. Nitrites (NO2) is very toxic to fishes when cycling or failed to cycle. Nitrates (NO3) are not toxic to fishes if kept 20ppm or lower but with higher numbers of nitrates in water are harmful (toxic) to fishes in the long term.
But no worries, been getting those two mixed up when i first joined the hobby and did no know bout ammonia either :)
 
20 ppm of nitrite would mean your entire cycle crashed and your fish is likely dead. You should also have off the scale ammonia.

So, please, recheck what you posted as suggested.

Moreover, the way a nitrate kit works is that it converts the nitrate into nitrite and then measures that. This is only relevant if you actually have nitrite. And it is mostly relevant when the nitrate reading is low. If you had 20 ppm of nitrite your nitrate reading could be mostly that.

I have been at this cycling stuff for two decades and I still catch myself making the same mistake with the i and the a. My mind says trite but my fingers type trate.....

There is chemistry at work re cycling our tanks. Things follow a progression. Part of that is nitrite is not there at first, then it appears, rises, peaks and comes down to 0. During this ammonia has showed up and then zeroed out. The change from rising to falling nitrite numbers happens after ammonia zeroes. This mean the most nitrite created /day has reached its peak for the current ammonia load in a tank.

You did not give us any info on most of this. But I am thinking your nitrite numbers were moving down not up?
 
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