How much NO3 in tap water??

[Splendid Warrior]

Hey guys,
I was puzzled why the NO3 level in my tank remains at 20ppm before and after water change. So, I tested my tap water with Sera test kit today and it read 20ppm! This points to either a faulty test kit or I have been fighting a futile battle to lower the nitrate level in my aquarium.

I will get a new test kit and do another test tomorrow to ascertain the truth. But I think the test kit I used is OK and I really do have high nitrate tap water. Looks like I have to use a DI unit now.

How much NO2 you guys have in your tap water? I live in Pasir Ris by the way.

[GaspingGurami]

Great for planters then! every top up gives the plants a booster jab for growth.

[Puffer]

Great for planters then! every top up gives the plants a booster jab for growth.

But don't you think this is abit too high even for heavily planted tank? I'm facing the same situation too and i'm residing in Bukit Merah. Seems like have to do wc daily.

[vinz]

You need to be sure of the readings. Because if you are not, your plants are going to starve.

Test the kit against a test sample. If a pail of tap water is at 20ppm NO3, dose another 10ppm and see if the kit register 30ppm. That will tell you whether the kit is stuck on the 20ppm reading. But you don't know whether 20ppm is the actual reading or it is a fake buffer.

Another thing to try, don't do your normal water change and don't dose your usual NO3. See if the plants will take it up.

Also, if you are not dosing NO3, the NO3 levels should go down, because the plants should be using it up.

If you are really getting 20ppm NO3 out of the tap, it's not a bad thing. if you know that 20ppm is going in your tank at every water change, then adjust your NO3 dose accordingly. If NO3 levels are going down thru out the week, then top up the NO3 levels. Should be less actually, because you are not changing 100% water. If you change 50% of water then, only 10ppm of NO3 is being ADDED to the tank.

[|squee|]

Seriously I wouldn't care... fish can live in nitrate levels much higher than that if I'm not wrong.

The so called recommended range of values is for optimum conditions for fish, like breeding, I always feel.

[vinz]

I don't think he's worried about the fish. More about the nutrient balance for the plants and to beat algae.

[Splendid Warrior]

You're right Vince, I'm not trying to eradicate NO3 completely but create an optimum environment for both flora and fauna.

[|squee|]

Ah I see, but plants are still fine with 20ppm of nitrate imho!

[Splendid Warrior]

Ah I see, but plants are still fine with 20ppm of nitrate imho!

... but fishes won't like that too much right?

[Splendid Warrior]

Its official, the NO3 level in my tap water is 20ppm. I bought a bottle of distilled water and tested it with my Sera test kit and the result was negative.

That would mean that I have been replenishing the NO3 in my tank with every water change when I wanted was to lower it.

What I intend to do now is to use 60%-70% deionized water mixed with my tap water for my tank and see what happens. Any suggestions will be most welcome.

[valice]

That's not necessary since you are having a planted tank... Why you want to lower NO3 levels?
20ppm is the target amount for the EI people... Hmmm...

[vinz]

... but fishes won't like that too much right?

Some sites say fishes are ok with NO3 up to 200ppm... but that's pushing the envelope. 20ppm is fine.

Its official, the NO3 level in my tap water is 20ppm. I bought a bottle of distilled water and tested it with my Sera test kit and the result was negative.

That would mean that I have been replenishing the NO3 in my tank with every water change when I wanted was to lower it.

What I intend to do now is to use 60%-70% deionized water mixed with my tap water for my tank and see what happens. Any suggestions will be most welcome.

Your distilled water test only determines that the 0 is correct, but is the scale correct?

If your tap water is 20ppm NO3. Then changing 50% of the tank water will mean adding 10ppm. Perfect in my opinion. Over time, the water changes and plant consumption will bring NO3 levels in your tank down. No need for de-ionized water, etc.

Don't worry too much about the NO3 levels you're getting. They are fine. Just adjust your other nutrients to match.

[Splendid Warrior]

Thanks for the recommendations guys. Appreciate it. I guess I'm always a reefer at heart and for my sps tank 10ppm of NO3 is 10ppm to much. But after hearing what you guys said, I think I'll hold on to my horses on the DI water.