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High nitrate

Saman

Member
Joined
10 Nov 2020
Messages
110
Location
London
Hi there, I have read through a few posts on high nitrate but none quite match my situation. My tank is about 6 weeks old and uses 85% RO and 15% tap. The nitrate reading is bright red - I’ve never seen a reading so high. The tank is high tech, 70 litres and heavily planted and the fertiliser is evolution aqua 4 mils a day but I’ve dropped to 3 mils. I’m seeing some green hair and brown algae too. I know I should try the DIY fertiliser route but I’m not ready to at this point. I’m hoping it’s just because it’s a new tank and it will calm down soon but I’m also wondering if I’m dosing too much fertiliser and if I should try seachem purigen to help. I’m doing water changes every few days now but it just shoots back up. Thanks for your help!
 
Hi @Saman Is it likely your tank is not yet cycled (6 weeks is not an awful lot) - are you doing frequent WC's ? ... I am running both my established tanks at very elevated Nitrate levels (always did) - in the +40 ppm range (also dosing Nitrogen as part of Tropica Specialized , Evolution Aqua contains Nitrogen as well) even with 40-50% weekly WC's... Plants and livestock in both tanks seems to be thriving. I totally stopped worrying about Nitrate, Phosphate, Potassium levels as long as they are not low(!) and as long as plants and livestock are happy with no sign of distress. I am not saying you shouldn't be however... I filter over Seachem Purigen as well (changing and regenerating every two week - but only 2 or 3 times until I disregard and replace) Purigen is not doing much for the nitrate levels in my experience.
Cheers,
Michael
 
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Hi saman,

It could well be the Tropica soil that's still leaching amonia that's giving you high nitrate readings, that's assuming the test kit is accurate.

I don't believe you have any fish in that tank so wouldn't worry about it to be honest. Just do more water changes, 2~3 50% per week and you should see it settle down.
 
@MichaelJ yes this could be it - I did a full month with no livestock and a fully mature filter then added some fish when nitrite and ammonia were zero. No sign of distress in the fish yet...
 
From the journal thread that @John q kindly linked to;
"Thank you - I increased the light to 80% over a month from 50%. I might reduce back a bit then."
What is the light at now?
 
Hi all,
Purigen is not doing much for the nitrate levels in my experience.
It is to do with <"the size of particle">, NO3- is an ion and many <"orders of magnitude smaller"> than the particles that Purigen would filter out/ bind. I'm not a Purigen user (I like tank water with some tannins) and I have a real issue with <"Seachem's advertising strategy">.
I have this tank in the journal section
<"The tank looks great">, and all those plants will reduce NO3 levels over time.

The way I look at is if the fish look happy and the <"plants are growing"> you are good, nothing else really matters.

Water changes are your friend and the fish will thank you for it, regardless of the nitrate test readings.
<"Same for me">.

I'm not a <"great fan of nitrate tests">, but I like <"conductivity meters">.

The way I use the meter is, when you are happy with plant and fish health (so now in your case), you take a conductivity reading. After that take one or two a week, once you've got a few readings look at trends and if the trend is going up, change a bit more water. After a couple of months you should have a <"conductivity datum range"> which is in the <"Goldilocks zone">.

cheers Darrel
 
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Hi all,

It is to do with <"the size of particle">, NO3- is an ion and many <"orders of magnitude smaller"> than the particles that Purigen would filter out/ bind. I'm not a Purigen user (I like tank water with some tannins) and I have a real issue with <"Seachem's advertising strategy">.
@dw1305 Agreed - virtually no denitrification ability (and not sure I would want it to anyway). The reason I use Purigen is for the water polishing - I do think that is real. I've always been somewhat hysterical about sparkling clear "neutral looking" water... yet, I have quite a bit of Malaysian ornamental driftwood for decor and the Purigen is doing a good job at keeping the tannis down (more effective than the active carbon I used to use back in the old (80ties) days).
I don't agree with this particular conclusion about Purigen pertaining to water polishing ability. I can definitely tell the difference when my Purigen bags have lost their "charge" and my water starts to "murk up" and loose that "neutral looking" clarity. But I do agree that it's heavily overpriced for what it is - and if someone would come up with a similar DIY solution at a fraction of the price I would use that in a heartbeat.

Cheers,
Michael
 
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While nitrate tests may not be the most accurate, I find my Sera test to behave in a consistent manner -for example, if I test before and after a 50% WC, the tests go from orange to yellow, rather than say, orange to dark red.

But assuming that I cannot know what exactly is the nitrate level behind that 'colour' would consistency in nitrate levels as shown in the colour of the nitrate test be a desirable goal? i.e. it would be undesirable if every day the nitrate test showed a different colour?

For example, if you are dosing more nitrogen daily than your plants need, would this result in your nitrate test moving from yellow to orange to red... and is this day to day variability of nitrate levels undesirable, rather than the actual level?
 
Hi all,
I don't agree with this particular conclusion about Purigen pertaining to water polishing ability. I can definitely tell the difference when my Purigen bags have lost their "charge" and my water starts to "murk up" and loose that "neutral looking" clarity.
I think the comments in <"pink tint"> are proof that Purigen is filtering out particles of a certain size.
I find my Sera test to behave in a consistent manner -for example, if I test before and after a 50% WC, the tests go from orange to yellow, rather than say, orange to dark red.
Yes, you are right consistency is the important bit, even if we're not entirely sure about what those levels really are.
For example, if you are dosing more nitrogen daily than your plants need, would this result in your nitrate test moving from yellow to orange to red... and is this day to day variability of nitrate levels undesirable, rather than the actual level?
I'm not sure that the level of NO3- is ever really a problem in a planted tank. Have a look at <"Salvinia auriculata......."> and linked threads. I don't often <"measure NO3- levels in the tanks">, I just use a water conductivity datum range and the <"size and leaf colour of a floating plant">.

cheers Darrel
 
Hi all,

It is to do with <"the size of particle">, NO3- is an ion and many <"orders of magnitude smaller"> than the particles that Purigen would filter out/ bind. I'm not a Purigen user (I like tank water with some tannins) and I have a real issue with <"Seachem's advertising strategy">.

<"The tank looks great">, and all those plants will reduce NO3 levels over time.

The way I look at is if the fish look happy and the <"plants are growing"> you are good, nothing else really matters.


<"Same for me">.

I'm not a <"great fan of nitrate tests">, but I like <"conductivity meters">.

The way I use the meter is, when you are happy with plant and fish health (so now in your case), you take a conductivity reading. After that take one or two a week, once you've got a few readings look at trends and if the trend is going up, change a bit more water. After a couple of months you should have a <"conductivity datum range"> which is in the <"Goldilocks zone">.

cheers Darrel
This is an interesting read in regards to the Purigen. I only used it for the first time in the last month and honestly... I haven't noticed any difference. In my nano tank, the quantity I added is well overkill and it does nothing for my nitrates or my water clarity. Everything is the same.

In my large tank, I had tannins from the wood but I just kept doing water changes and within 2 weeks it was gone. After 2 months I tried the Purigen because of the claims, but again...no discernable difference.

I'm not calling anyone out or saying your experiences aren't valid, these are just mine. From my experiences in the past, I've not used any chemical filtration and sometimes even no 'specific' biological filtration (sponges only) with no ill effects.

TL/DR: I'm going to save my money for other things.
 
Hi
If you are overly concerned about high Nitrate levels.
You can use this below method over a few months!
hoggie
 
Hi all,
I'm going to save my money for other things.
If you are overly concerned about high Nitrate levels.
You can use this below method over a few months!
Same for me, it is back to the <"coffee and the froth">. I'm happy with the techniques I use. They have a <"basis in science"> and I've personally used <"them successfully for ~15 years">.

Others may follow <"a different path"> and be equally successful.

cheers Darrel
 
Hi all,

I think the comments in <"pink tint"> are proof that Purigen is filtering out particles of a certain size.
@dw1305 I agree.
I'm not sure that the level of NO3- is ever really a problem in a planted tank.
Although it seems to go against common belief, I have come to that conclusion as well. I've been in the +40 (or 80 ppm) range for a long time now (according to my API kit - very hard to tell the difference between the red patches indicating 40ppm and 80ppm) there are probably limits for sure, but my weekly WCs take care of that I suppose. Plants and fish are doing well, I have virtually no algae - and my remarkably thriving frogbit looks good.

This is an interesting read in regards to the Purigen. I only used it for the first time in the last month and honestly... I haven't noticed any difference. In my nano tank, the quantity I added is well overkill and it does nothing for my nitrates or my water clarity. Everything is the same.

In my large tank, I had tannins from the wood but I just kept doing water changes and within 2 weeks it was gone. After 2 months I tried the Purigen because of the claims, but again...no discernable difference.

I'm not calling anyone out or saying your experiences aren't valid, these are just mine. From my experiences in the past, I've not used any chemical filtration and sometimes even no 'specific' biological filtration (sponges only) with no ill effects.

TL/DR: I'm going to save my money for other things.
@Courtneybst I think my experience with Purigen is mainly the ability to remove the tannins (what I call "murky" above) from my driftwood. I would claim that by removing the tannins you also improves overall water turbidity, but how much suspended solids Purigen removes is questionable. Seachem claims some collateral benefits such as reduction in Ammonia and Nitrite ("Does not directly remove this contaminant, but use can indirectly lower levels" as they put it), I suspect that is probably just from the aerobic bacteria that will inevitably grown on the filter media. I am fairly pragmatic about the products I use in the hobby and I would love to save the money if someone could point me to a DIY / cheaper solution.

Cheers,
Michael
 
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It is to do with <"the size of particle">, NO3- is an ion and many <"orders of magnitude smaller"> than the particles that Purigen would filter out/ bind.
I seem to remember that they used to simply claim that it reduces nitrate. But they are currently claiming that it reduces dissolved organics, which can lead to increased nitrate. That might be more accurate, or a better explanation, and could explain why people who bought it to 'reduce nitrate' often found it did not have that effect.
Seachem
 
Hi all,
But they are currently claiming that it reduces dissolved organics, which can lead to increased nitrate.
It is a technically correct answer, because all organic matter must contain some organically bound nitrogen, but the <"contribution of, say tannins">, would be absolutely minimal because they contain very little in the way of nitrogen in the first case (they have a very high C : N ratio), which is why they are persistent and don't biodegrade.

cheers Darrel
 
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