High nitrate NO3 value

[blueberlin]

After just completing a 90% water change, I get a nitrate reading of roughly 70 mg/l - how is that possible???

 

[Kal El]

Hello Eva,

Did you test the water straight after the water change? Also, why did you perform a 90% water change? It's rather unorthodox if you do not have high ammonia readings.

Jay.

 

[blueberlin]

Apparently I am in the middle of a full-blown cycle. I was using those stupid, accursed dip strips (I spit on their makers!) and they were telling me that eeeeverything is just fiiiiiine and dandy. And my guppies started dying and within hours were covered with fungus. And then two of my larvae were attacked by the fungus, and one of the smallest just kind of shrivelled up and started dying. I lost all 3 larvae and 4 guppies and so went out and bought the chemistry set test lab. Sat up last night testing the water and discovered that all values were haywire. High nitrite (between 0.025 and 0.5 mg/l), high nitrate (between 40-60 in one, 60-80 mg/l in the other aquarium). Ammonium 0.1-0.2 mpg/l. This morning we - the whole family joined in - drained 90% of all water in both aquaria and added fresh. Then they wanted to see how the test kit works so we tested the two aquaria and the tap water. (Tap water incidentally also shows a nitrate reading but we are undecided as to the amount, either 1 or 10 mg/l.) Results of testing was that fortunately nitrite is gone but nitrate is still sky high. How is that possible with 90% fresh water???

 

[Kal El]

Ammonium 0.1-0.2 mpg/l

You should really be testing for ammonia rather than ammonium. Although both are toxic; ammonium is less toxic than ammonia. Does the bottle say NH4/NH3?

Then they wanted to see how the test kit works so we tested the two aquaria and the tap water. (Tap water incidentally also shows a nitrate reading but we are undecided as to the amount, either 1 or 10 mg/l.) Results of testing was that fortunately nitrite is gone but nitrate is still sky high. How is that possible with 90% fresh water???

I think you've answer the question for yourself here. The tap water contributed towards the high nitrate reading. Also, you never answered my first question: Did you test the tank water straight after the water change? Perhaps I just missed your answer because I'm just too tired from all the study
If you did test straight after the water change, you could be getting false positive (or inaccurate) results for nitrate.

Jay.

 

[blueberlin]

The test only has a test for NH4, not NH3.

Yes, I tested immediately after the water change - how does it work that this can give me a false reading?

Other than that, a low reading in the tap water should not result in a high reading from the tank, should it?

 

[Kal El]

You should really consider purchasing a test kit for NH3 and not NH4

A false positive/inaccurate reading could have come about because you did not allow all the organic matter to settle before you tested the water. Have you tried testing the water again? Or did you test it just before? Try to wait at least 24 hours before testing your water.

Jay.

 

[blueberlin]

I last tested it last night. I'll test it again tomorrow morning. I did not test it right before chaning the water because that was the first thing I did this morning and I wasn't thinking properly yet. I may not be thinking properly even now.

Thanks for your help, Jay. I didn't realize that the test can give a false reading.

 

[Kal El]

Hello Eva,

I just remembered something else regarding the testing of your tank water. It is imperative that you conduct the test accordingly because a badly run test can also result in inaccurate readings. Therefore, I will raise the following points and hopefully you are already aware of them:

- Read the instructions carefully; even if that is just a given

- Rinse the test tube before and after each test. Rinsing should be done with tank water and not any other source. Also, you should never pour the rinsewater back into the tank because of the chemicals that are present in the test tube.

- Never take water to be tested from the surface of the tank because this water will most likely contain more dissolved gases and extra lipids/proteins that may contribute towards inaccurate readings.

- Make sure that the bottom of the meniscus (water line) within the test tube is parallel with the designated 5 mL line marked on the test tube. It is important that you are at eye level with the menicus because it will look different if you are hovering above/below the menicus.

- When dropping the test solution into the test tube ensure that excess drops do not touch the surface of the test tube because these test solutions utilise titration as their primary method. Titration is an analytical method and 'every drop counts'. Thus, the test solution drops should be uniform throughout

- When shaking the test tube, don't use your thumb as a substitute for the cap because your thumb will contain sweat (i.e. salt) and lipids that will once again give inaccurate readings.

Yes, that's all I have to add. Hopefully your nitrate reading has corrected itself.

Jay.

 

[blueberlin]

Hi Jay!

Thank you dear, you have taught me something indeed.

- Never take water to be tested from the surface of the tank because this water will most likely contain more dissolved gases and extra lipids/proteins that may contribute towards inaccurate readings.

The rest I did/didn't do, as appropriate. As a matter of fact, not dumping the rinse water back into the aquarium was one of those rare moments where I actually had the idea before I had done something stupid.

Just waking up now and will test again as soon as I can focus eye-hand coordination.

-Eva

 

[blueberlin]

Well that took awhile but here are my values for Aquarium 1, Aq. 2 and tap water (I tested phosphate just because it was fun to play with the little spoon. Different results for each water sample.). Last wter change was 90% water change roughly 24 hours ago:

Aq. 1 (new aquarium, less than 1 month old, containing approx. 20 guppies/platys, 1 adult axolotl, some snails, and a few floating live plants):

KH: 12 °dKH
GH: 14 °dKH
pH: 8

NH4: 0.1-0.2 mg/l
NO2: 0 mg/l
NO3: 40 mg/l

PO4: 1.0 mg/l

Aq. 2: Several months old, containing 1 adult axolotl and some snails:

KH: 10 °dKH
GH: 12 °dKH
pH: 8

NH4: 0.4 mg/l
NO2: 0 mg/l
NO3: 60 mg/l

PO4: 1.5-20 mg/l

Tap water:

KH: 12 °dKH
GH: 12 °dKH
pH: 7.5

NH4: 0.2 mg/l
NO2: 0 mg/l
NO3: 10 mg/l

PO4: 0 mg/l

Is anyone experienced enough to put this information together to form a picture of what is going on in my water world?

Thanks so much,

-Eva

 

[Terri9967]

Good Morning Eva

I too learned from this post. I didnt realize to take samples from bottom of tank and not straight from top of water level. I am nervous now to do my daily water test as I was doing wrong and I may get different readings now that I know to take the sample water from lower in the tank...

 

[Lisa]

I'm not that knowledgeable, but for what it's worth, those nitrate levels are fine, the nitrite is obviously fine, it's only your ammonium that looks a bit high. That could be a consequence of the very large water change, or a source of contamination from eg uneaten food, but I'm sure you don't have anything like that. So you need Jay .

 

[blueberlin]

I'm not that knowledgeable, but for what it's worth, those nitrate levels are fine, the nitrite is obviously fine, it's only your ammonium that looks a bit high. That could be a consequence of the very large water change, or a source of contamination from eg uneaten food, but I'm sure you don't have anything like that. So you need Jay .

I'm afraid I'm in the middle of a cycle.

Ok ladies, help me out here - Jaaaaaaay!

 

[Kaysie]

The fastest way to cycle a tank is to leave it alone. If possible, rehouse your axolotls in a temporary house (bucket, bowl, rubbermaid tub, etc), and whenever they poop, dump that in the tank. Otherwise keep your tank running as it is now and continue to monitor water quality.

 

[Kal El]

Hello Eva,

So I've noticed that you enjoyed mucking around with the phosphate spoon I've never tested phosphate before but I can most certainly give you some background information on it.
To have phosphate in your aquarium is absolute necessity (i.e. phosphate can act as a buffer which prevents pH swings). Phosphate comes in two forms in your aquarium:

1. organophosphates (which can be used by animals) and;
2. orthophosphates (which cannot be used by animals but can be used by algae).

The test kit that you have Eva, is only testing for orthophosphates. Orthophosphates can be utilised by algae and the same goes with nitrate, thus a low phosphate reading is always a good indication. Keep in mind though that algae can survive on an orthophosphate level of 1 to 10 ppb (parts per billion). Your test measured 1.0/20 ppm for orthophosphate. The main reason as to why you do have algae proliferating in Aq. 1 at an alarming rate is because you have plants. Plants have the ability to store orthophosphates, thus starving the algae. Good job

Aq. 1 (new aquarium, less than 1 month old, containing approx. 20 guppies/platys, 1 adult axolotl, some snails, and a few floating live plants):

KH: 12 °dKH
GH: 14 °dKH
pH: 8

NH4: 0.1-0.2 mg/l
NO2: 0 mg/l
NO3: 40 mg/l

PO4: 1.0 mg/l

NB 1 mg/L = 1ppm therefore 40 mg/L = 40ppm

I've noticed that you have been testing for ammonium. I recommend that you purchase a test kit for ammonia instead because ammonia is more toxic than ammonium. Keep in mind that the toxicity of ammonia generally increases with increasing pH. A NO3 reading of 40ppm is perfectly fine. Moving onto your GH and KH readings: I personally do not check KH because I do not feel that is necessary but if you would like me to go through it all, I'm more than willing. Just not now coz it's 3:15am

Your GH reading is rather high to say the least. In fact it wasn't even on the chart that I have. I had to produce and linear equation and resort to extrapolation to figure out the value of 14 °dKH in ppm, which is 250.6ppm. Such a high reading indicates that there are plenty dissolved salts in your tank which can be bad, especially in terms of osmoregulation. Have you been supplementing your tank with any salts or crystals?

A similar explaination can be applied to aquarium 2, aside from the PO4 reading which I explained before.

Anyway, I hope all of this made sense :happy:

Jay.

 

[blueberlin]

Hi Jay!

Admit it, you never sleep.

I'm with you so far. I have not been adding anything to my water. Unfortunately I seem to have cruddy water coming from the tap. It has, for example, 10 mg/l nitrate straight from the tap, so I will never be able to get rid of nitrate comlpletely. I don't know if I mentioned that we will be moving this summer? Anyway, at that point I will start learning about having live plants in an aquarium as I assume they will help at least some. Right now I'm just starting to get my head around the whole aquarium/axolotl thing and could not possibly begin learning something else.

Could the minerals be coming from the sand in Aq.1? It's aquarium sand, bought at an aquarists shop.

Thank you,

-Eva

 

[Kal El]

Admit it, you never sleep.

You're right there I can't afford to sleep at this point in time anyway because my exams are around the corner and I'm one of those people who like to watch the work stack up and then panick when it comes to the crunch.

Could the minerals be coming from the sand in Aq.1? It's aquarium sand, bought at an aquarists shop.

If this sand is marine sand, then definitely yes. Even if it is a parital mix between marine sand and play sand, it will contribute to the overall GH reading. I'm still a bit unsure about whether you GH reading is detrimental to your axolotl(s) health. I will however check the GH reading for a standard salt bath and if your GH reading for your tanks match/come close to that of the salt bath, then you might be in a bit of trouble. What is the volume for your tank? It will be easier for me to calculate the GH reading because I have to take into account dilution factors.

Regarding the NO3, that is a bit of a bummer However, you can add a Nitra-sorb to the buckets of tap water before you add the water to the tank. Nitra-sorb is an ion exchange resin medium that absorbs nitrate. I do believe, you will have to leave the Nitra-sorb in the bucket(s) of tap water overnight/couple of days. So that's one problem solved

Jay.

 

[blueberlin]

Aq.1 is 120x45x50 cm
Aq.2 is 100x36x46 cm

I didn't realize you are a student; I thought you were a professor.

The sand is not a mix, at least I didn't mix anything with it. I went to the pet shop where they sell stuff for fish (plastic plants, the yellow jars of flakes, etc.) and said I need aquarium sand and he gave me this freakin' heavy bag of white(ish) sand in a clear plastic bag.

-Eva

 

[Abrahm]

I've noticed that you have been testing for ammonium. I recommend that you purchase a test kit for ammonia instead because ammonia is more toxic than ammonium.

Eva doesn't need to buy a new test kit. Testing for ammonium is perfectly fine as the vast majority of the ammonia will form ammonium under standard aquarium conditions. This is a standard equilibrium situation.

Your GH reading is rather high to say the least. In fact it wasn't even on the chart that I have. I had to produce and linear equation and resort to extrapolation to figure out the value of 14 °dKH in ppm, which is 250.6ppm.

Most of the materials I've read quote 14 degrees of general hardness as "fairly hard." If I were you I would have just found the conversion for degrees of hardness into ppm instead of making a linear regression. You would have saved some time for studying.

If your tank is cycling and you need to leave the animals in there you will need to test regularly and possibly perform frequent water changes to keep levels suitable for the animals.

The easiest explanation for why your nitrate was so high after a water change was that the test tubes weren't well washed. Rinse your test tube thoroughly, and I see no reason why you can't use tap water on them.

 

[Kal El]

Hello Eva and Abrahm,

I didn't realize you are a student; I thought you were a professor.

Thanks for the dimensions. I will get back to as soon as possible.

Nope. I'm only in my 20's (still in Uni.) and I personally have never met a professor who is in their 20's. But if there are some out, well, more power to them!

Eva doesn't need to buy a new test kit. Testing for ammonium is perfectly fine as the vast majority of the ammonia will form ammonium under standard aquarium conditions

This may be the case matey but the ammonia/ammonium ratio is effected by pH which is why I told Eva to purchase an ammonia test kit. Of course the choice is entirelly up to her.

If I were you I would have just found the conversion for degrees of hardness into ppm instead of making a linear regression. You would have saved some time for studying.

Thanks for the heads up but I generated the linear equation on a TI-84 Texas Instruments calculator so it only took me less than a minute.

The easiest explanation for why your nitrate was so high after a water change was that the test tubes weren't well washed. Rinse your test tube thoroughly, and I see no reason why you can't use tap water on them.

Eva mentioned that she did wash the test tubes accordingly. The reason why you shouldn't wash the test tubes with tap water is because this is form of titration. You are taught in your high school years that you should always wash glassware (i.e. graduated pipettes) with the solution that is be analysed. Also, Eva has nitrate in her tap water which will contribute towards an inaccurate reading.

Jay.