Can't figure it out...Nitrite just keeps coming back

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julielynn47

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I have fighting this for quite a few weeks now. I can't figure it out. The tank will appear completely cycled, for 2 or 3 weeks, and then the nitrites are back. Ammonia is 0 but I just can't get rid of the nitrites.

Twice now this tank has appeared completely cycled or it would not have shrimp in it now.

As a last resort effort I decided to use Purigen. I called Seachem and spoke with someone there. They told me that Purigen would not get rid of the nitrites that are in your tank, but if you got rid of the nitrites with a water change, then added Purigen to the filter, the Purigen would then keep the nitrites from coming back.

Well, I am here to tell you...it did not do that. For a few days it did. For a few days I had no nitrites in the tank. Then today I noticed a dead shrimp. I thought what the heck? They all seemed fine last night. So I get my test kit and test ammonia and nitrite. Ammonia=0 Nitrites = .50

So here I go again... I just do not understand why this tank still has nitrites.

Anyone have any suggestions?
 
Thats kind of unsual.

Are the shrimps behaving oddly at all or are they are their normal cool selves?

Is the nitrite returning back at regular intervals?
i.e just after weekly water changes or tank/filter maintenance cleans

Whats the tank and filter again?
sorry, I bet I know this but just can't recall right now.
 
It sounds like something is inhibiting the nitrospira colony growth.
As Ch4rlie has suggested posting your tank and filter info, including your filter bio-media as well as your maintenance (water changes/filter cleaning, etc) would be most helpful. For water changes, have you tested your source water?
Are shrimp the only thing in your tank? Also, as mentioned, is there any activity you can think of that corresponds to the nitrite increase?
 
It is the 10 gallon tank that I set up for shrimp. I do have a nerite snail in it as well.

I do a 50% weekly water change. It has a HOB filter. Inside the filter is the regular stuff.... bio media, a few bio rings, and a piece of filter felt 50 micron size. And of course the Purigen, which is not helping at all as far as I can tell. I don't have carbon in it at all.

The shrimp act like normal cute little shrimp, except for the one I found deceased of course. I had 17 in the tank. It is hard to know for sure if all 17 of them are in there as they are hard to pin down all at once. LOL But the one I found today is the only dead one I have seen so far.

And the last 3 days the water has been cloudy again. Like a bacterial bloom is going on. I don't know however if that is what it is or not. As for the Purigen hurting the colony, people say that it won't, but I have not been totally convinced, so the Purigen is the last thing the water touches before it returns to the tank. The water does not flow through the Purigen then through the colony. ( As I type this, it sounds silly of me to think that would matter, but in my mind it did...)

There is not any certain activity at all that triggers it as far as I know. I only got the Purigen to see if it would help and obviously it did not. Not to say that Purigen is not good stuff, I am sure it is, but it didn't help me with this issue
 
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Oh forgot to add, I have also seeded the filter, probably a month and half ago at least, with some bio rings and a piece of bio media from my established 55 gallon. I also used 2 bottles of SafeStart. Not at the same time. I used one, and finally thought it was cycled, but no. Then I used another bottle and thought the same, but nope. And I didn't use the SafeStart until after I had tried to fishless cycle without it, that was back in August, and thought it was almost done when all that went south.

So this has been a true test to my patience for sure.

This morning it is still cloudy. Haven't taken any water readings as yet. Coffee first.... :)

Okay, coffee done... Ammonia = 0 Ntrites = 0 Water still cloudy like a bloom is going on.

I sure wish I could figure this all out.
 
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The bloom is basically a bacterial bloom, as you know anyway.

So that means the cycle has had spikes for some reason.

Could be down to purigens or over cleaning of tank/filter are the two most likely suspects.

Do you change any of the filter media regularly at all?

And if you could provide the exact brand and type of the purigens you use (a pic might help), this may help us in finding out more about this product online and if potentially has anything that may effect your tank.

The use of two bottles of safestart should not have had this type of effect but am not entirely 100% (will research a bit more when not on my lunch break :p )
 
Thank you. I am about ready to pull my hair out.

It is Seachem Purigen. I never throw away the bio filter or the piece I seeded with, or the bio rings I seeded with. I have thrown out some filter floss that was too nasty to reuse and a piece of filter felt that was also nasty.

Maybe I should have just rinsed it out, but I really think the floss would have just fallen apart if I had done that. And besides, the floss and the felt were relatively new additions. They do clean the water really well to have gotten so nasty so quickly. And I had this issue twice before I even started using it. So I don't think that is what caused this latest episode.

I have just this morning ordered a new filter system for this tank. I wanted something that would allow for more room in the housing for more media. The one I have is so small I can hardly get anything in it. I want one that is HOB but more like a canister. That way I can layer what I want in it and hopefully get better flow actually through the media instead of around and over the media the way it is flowing now. Will this help? Who knows? But I am giving it a try anyway.
 
Replacing the filter floss if fine, I do that every week on my own filters anyway. Just as long as your main filter media remains.

Seachem Purigen, ok, Seachem are a fairly good brand and would be a little surprised if it will cause any issues if instructions are followed exactly, no overdosing etc.

Have had a quick look online regarding seachem and if has any effects on nitrite levels, remember that I am no scientist at all, I could not find any adverse effects on tanks regarding ph, kh, gh and on ammonia as well as nitrite levels. The only effect, as is stated its for, is nitrate levels. So on that basis, I would be fiarly confident it probably does not have an effect on your bacterial colony or on nitrite levels.

That however does not mean it won't affect anything in the tank other than nitrate without someone with considerable knowledge on these types of matters.

I for one, am always hesistant on adding anything other than dechlorinator, water and certain ferts to a fish tank as every chemical or product usually has an effect on the stocking or tank/filter bacterias etc.

Maybe a suggestion is to try a week or two without the purigen and see if this has any effect on your nitrite levels. OK, your nitrate may rise but with normal 50% weekly water changes, this will lower nitrate levels.

This is somewhat of a touchy matter with some members, but I always felt that levels of 10 - 40 ppm nitrate is an acceptable level but anything above this long term is asking for trouble with your stocking's health. Of course anything below 10ppm nitrate obviously is much better but not always achievable in some tanks due to a number of variables.
 
Yeah, Seachem does not say it will take away nitrates. I was not even thinking nitrates though. I just thought it would maybe help with this issue. You see, I was having this issue "before" the addition of the Purigen,. Taking it out most likely will not help at all, since the issue was going on prior to adding it.
 
But if it won't harm anything then I will just leave it in and see what happens. I am all for a healthy tank with " nothing but water added" but I also see no reason to not use things that help do different things. And yes, I know it is a touchy subject with some LOL

But good gosh, as much as I love my tanks, I can't change the water in them over and over everyday. Sometimes I just think a tank needs a little more help...but that is just me
 
This is a 10g tank...I would go to a simple single sponge filter. With shrimp this should be fine.

I'm not going to guess at other issues, but will just mention that I have had a problem in one tank for over a year. Cloudy/hazy water (not bad, but obvious). Turns out to be an organic-related bloom, bacterial or more likely diatom. Neale Monks assisted me to ID the issue, but finding the cause has eluded us. I won't go into all that, but I may be able to draw some parallels.

The brown gunk in the filter media, and the Purigen, are organics. Purigen supposedly removes these. I tried it, even double the pads, and it certainly removed organics but was totally unable to completely handle them, they are so massive. I also tried a similar product, Poly Filter, and it too became black-brown with organics in a week, but had little effect on the bloom. Fortunately, what I have is harmless to fish, it just looks unsightly. But it comes and goes; now the tank is clear and has been for several weeks. There is nothing special in the filter, but I am now cleaning it monthly and hope to see this improving things--so far it seems to. None of my tanks with sponge filters have this issue.

Remember that any chemical filter media will have an effect on water chemistry. That is what it is intended to do. And one thing I learned from my issue is that the slightest thing can have big consequences biologically/chemically within the confines of an aquarium. The simpler, the better.

Byron.
 
I agree with the simpler the better. I only got the Purigen to try to clear up the nitrite issue. Which is didn't. But anyway...

I have not done a thing different except for the Purigen ( which didn't help, like I said.) So I can't figure out why this keeps happening. This is actually the first time for the cloudiness. Just not the first time for the nitrite spikes.
 
I can assure you that Seachem Purigen is not related to your cloudiness issue.
Purigen is simply a synthetic resin with an affinity to adsorb dissolved organic nitrogenous compounds. The marketing suggests that this will reduce nitrates since the encapsulation interrupts the decomposition resulting in ammonia>nitrites>nitrates. However, I never found this to be accurate in that it never reduced tank nitrates for me.
As far as trapping fine organic compounds, I think (and as you have seen first hand) polyester filter floss does a very good job of this.
I think I would cut back on feeding and be patient as usually the tank will clear on it's own. If not, I might consider Seachem Stabilitiy, DrTim's Waste-Away, or Aquabella as all of these are natural bacterium products with strains of bacteria to [better] decompose bio-waste.
 
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The cloudiness I can be patient with, no problem. Nitrates, I can deal with, no problem. It is the nitrite spikes that are getting to me. I don't know what to do about them. I seriously have tried everything that I, at least, know to do.

This morning the reading are still good. Who knows how long that will last

I guess in time it will just correct itself. I don't know...
 
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So far so good on the nitrites. There are still at 0. Who knows for how long though.

The water is still cloudy, no idea why. It was crystal clear until a few days ago. I do remember, years and years ago, when I first set up my 55 gallon, that the water stayed cloudy for a long time. I didn't know why then, I do now. It was going through a fish-in cycle. ( I didn't even know what a cycle was back then ) But this 10 gallon tank appears to be cycled, or if not totally cycled, so close it might as well be. So I don't know. Very frustrating since I can't pin the cause down. If I had done something different then I could undo it. But I didn't do anything different.
 

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