Nitrite Spike

I came home last night to find my favourite fish dead in the tank. Did a water test and found my Nitrite had jumped. Couldn't figure out why, as had tested it only a few days before when I cleaned out my filter. Thought I might have removed too much of the bacteria culture, even though I cleaned them in tank water. Then I realised the filter was very weak. After I removed it, I realised I hadn't fitted it again properly after maintenance. Feel like an idiot for killing the fish.

However, can anyone tell me how to reduce the Nitrite to ensure no more deaths? I did a large water change and only fed the fish a little food. This morning it has dropped a little, but not a huge amount. Should I continue water changes until it drops right down or could this do more harm than good? If I should, what percentage change we talking?

Tanks in advance,
Lorcan

small water changes 10% daily is all you can do, to much and you'l restart the cycle over again. no one can say wat your success rate will be but just pray it works out

Xaribdis wrote:

Couldn't figure out why, as had tested it only a few days before when I cleaned out my filter. Thought I might have removed too much of the bacteria culture, even though I cleaned them in tank water.
Lorcan

Lorcan,

As far as I know you have the Juwel internal filter. When you say the above 'cleaned them' do you mean that you cleaned all of the media at the same time. The bottom two blue sponges must only be cleaned approximately once a year while the other coarser sponges every few months if that, but all on seperate occasions. Maybe I've misinterpreted you and sorry to hear about your fish.

Other than that follow the lads advice.

Dave

My ammonia is reading practically zero. It's not quite yellow on my test, but only slightest hint of green, so very low. Why do you ask? Could there be an underlying problem I have not thought of?
It's a discus tank, and the three darkest fish were almost black in colour, reckon they were/are touch-and-go. Probably shouldn't have jumped straight into discus, but they are so beautiful I couldn't help it! When I offered food, all but one ate, but not as greedily as they usually do. This morning I dropped in a bit and they were all at it like usual.
I'll keep up small changes, maybe 5% twice a day. That sound about right?
Sorry to hear about your power cut last year. Must be much worse when the problem is beyond your control.
Thanks again,
Lorcan

listen don't start wit the negativity, doubting yourself, we all make mistakes. you would of had ammonia first then the nitrites so you have bacteria working for you which is gonna speed things up, just stick wit 10% a day at once and keep testing it, i bet come a week you'l be sorted

Sorry Dave, missed your post earlier. Yeah, it's the Juwel internal. I cleaned all of them except the very bottom blue sponge. I knew I wasn't supposed to do all of them together, but thought it should be more frequently than that, so have done it quite a few times over last few months. Oops! It wasn't even really a major clean, just picked off any stringy dirt that might block it and then quick little squeeze in tank water. But I'll leave them alone for longer periods from now on.
Thanks for all the advice lads,
Lorcan.

why has this sponge only to be cleaned once a year, wats the point in it? shed some light people

I take the whole lot of media out and clean it with tank water till almost clear water comes out when squeezed, 15 minutes all back in, no problems no spikes, this is every 12 weeks.

Stock level will determine how often it is done and also the type of fish.

What I have done more that once early on in the hobby, is forget to plug the damn filter back in!!!

Sorry to hear of the deaths matey, lesson learned. Also I would change 10% every 3-4 hours to quickly reduce Nitrites safely if you want to save te fish left, damage from Nitrites is permanent so remove them as quickly as is safe for the fish, every spike reduces the fishs life span and immune system effectiveness.


Mark

How easy is it to set off another cycle? Can excessive water changes do that? I like to syphon the fish waste (how polite!) from the bottom of the tank two days in three to keep the tank clean, more aesthetic for myself and not have the fish swimming in their own waste. Each time it only equates to about 5-7% of total water volume. I actually quite like it, but is this far too much? Thought maybe the only problem was the filter, but could this have been exaccerbating it?

wat substrate are you using? gravel will hold a lot of nitrifying bacteria just like your filter, but considering people have bare bottom tanks your filter should cover it, let me get this straight, is it every second day you syphon or two days syphon one day break? i'd drop the latter, 5-7% every second is fine along side your weekly 20%

It's a medium-sized aquarium gravel, so give that a bit of a syphon to pick up the big pieces of waste about 3 times a week (about 5-7%) and then do a 20% change once a week. So, probably closer to every second day. When I hoover the gravel will the bacteria stay behind or is it easy to remove them by syphoning?

no, you will remove some but thats inevitable, just like cleaning your filter, which is why you never do both at the same time

I may not have read the replies correctly.....but how exactly were the filter sponges cleaned?

If you take a bit of aquarium water and wash the sponges in that (so long as the pH, temperature etc) have not changed then the amount of media-bound nitrifying bacteria removed should be negligible.
If, however, they were washed under tap water then there is a good chance of destroying too high a population of the bacteria....and those particular bacteria populations are slow growing and very prone to changes in water.

If you are keeping Discus, then I would recommend doing proper filter maintenance quite frequently...dirty filters will kill the Discus in ways other than by changes in nitrites/nitrates etc.

So, a few other questions....

could it be possible that the dead fish caused a rise in ammonia/nitrite? eg was it a big fish dead for a longish time?

I'm concerned about the ammonia....ammonia for Discus should be undetectable on a standard test kit.

What is the nitrate level? Under certain conditions, nitrate can be converted to nitrite.

pH? what is the pH?
What is the buffer capacity and hardness of the water? It is difficult to test for buffer capacity, but hardness is measurable and will affect buffer capacity and pH.

As for questions about water changes, for Discus try to keep it consistent. There are various methods: change a small amount very frequently, eg daily/2-daily (recommended for starting out); a constant change of water (not easy, and not really needed); or very large changes done once a week (but I would not recommend that method if someone is starting with Discus as it brings many risks if not done properly).
Discus have a high demand for quality food...and that demand is a big demand on a filration system.
Leaving Discus to the normal routine used for many other fish can lead to long-term problems.

On the cleaning sponges once a year....I'm a bit lost I must say as the gunge build-up may render the sponges pretty anaerobic and in a way that cannot be exploited (there are instances where anaerobic conditions can be exploited...but not if there is limited water flow).

ian

igmillichip wrote:

On the cleaning sponges once a year....I'm a bit lost I must say as the gunge build-up may render the sponges pretty anaerobic and in a way that cannot be exploited (there are instances where anaerobic conditions can be exploited...but not if there is limited water flow).

ian

Ian,

I have a very similar set up to the poster and simply repeated the advice given by Juwel themselves regarding the bottom finer sponges (to clean once a year or so).

I have my tank pushing 2 years and check those sponges from time to time for build ups of gunge and they still remain remarkably clean despite being never cleaned.

The poster is obviously meticulous regarding tank & filter maintenance so I assumed his bottom sponges are in a similar condition along with the fact his tank is much more immature than mine.

So Ian, good advice all round.

Dave

I would guess that if the sponges in the first stage of the filer are maintained routinely, then later stage may not need such routine work.
The main thing that concerned me was how exactly the sponges were cleaned? eg under the tap or not.

Is the bottom sponge you mention one of the de-nitrifying sponges (is it green with fluval filters)?

ian

Ian

This will explain it more clearly I hope!!


www.juwel-aquarium.de/en/filter_full.htm

Dave

hi sorry to hear about your loss, but i would always run 2 filter systems, esp. in a Juwel aquarium, the filter system IMO is not up to the general task (unless your keeping a low stock level) Esp. with discus i would alway rec. an external filter, far, far superior to internal IMO
Dont feed for 5 days or so and give your filter a chance to re-establish itself,the black sponge in the Juwel filter is carbon, this cannot be "cleaned" its chemical filteration and need to be replaced.
Hope it all works out!!

I will point to the fact that some people don't know how or don't bother stacking their media correctly.

You can trap the heavy waste at what level you wish.


My internal 450 has top to botton, top being te first to intake waste, upper tray : Microfibre, coarse sponge x2 Carbon foam x1
Lower tray : Course sponge x1, fine sponge x2.

Microfiber needs regular maint but saves much more maint on the 6 lower sponges, with the fine with hardly any gunk on it upon maint after about 12 weeks. A year, leaving s sponge that long will leave the pump at such a low throughput for a very long time.

Removing the gunk maximises flow, so the more maint and correct media layout will give an increased flow and therefor a higher filtration capability to your filter with the least amount of maint possible. If you clean media properly there is very little bacteria reduction and maximum aeration too which has benefits. All in all you should have the media out for no more that 5 minutes even with the largest externals, leave the cannister full and take out one tray at a time clean and stack, clean cannister, always prepare space and water first and get it done as quick as possible, all done back in, hey presto.

I feel a setting up and maintaining your media article in the air, article writers??

Always if possible and practical, run a secondary filter, even a small filter sponge attached to an airline will give you some tollerance in the event of a main filter failure or leak if you would be cr@pped out if it all died, I'd quit the hobby for some time if it happened to my Catfish collection.:angry:

Mark

DJK wrote:

Ian

This will explain it more clearly I hope!!


www.juwel-aquarium.de/en/filter_full.htm

Dave

Thanks dave, but is was a bit basic (soz) and wouldn't really explain much to someone who wanted to know about filtration (and I'm not on about the level of knowledge and science that I would normally go into either)

However, that description is just a box standard filter set-up. It does, however, re-iterate my point above about regular maintenance of the filter system at some stage of that filter system to avoid blockages.

Presumably, the sponges they are talking about in that link is the box-standard sponges for nitrification (and mechanical filtratio) as opposed to the ones Fluval also make for denitrification (I think you may have to buy them separately).

There probably needs, as mentioned above, something on filter set-up.
But, I was amazed to see that some of the modern filter kits are almost idiot-proof....
I recently had to buy an emergency pump but with 5 minutes to closing, the shop had one system even close to half what I needed....the Fluval U4....it was almost idiot proof to put the filter bits in (guess what?.....i didn't like being controlled by a manufacturer )

ian

Thanks for the replies everyone, I have been following all the advice (at least trying to, some of it is contradictory) and today my Ammonia and Nitrite levels are back down to zero, so happy days. It must have been my error of not fitting the filter back properly again. Very frustrating, but part of an unforgiving learning curve I suppose.
Thanks for all the advice again Dave, feels like you've taken me under your wing since I started. I'll definitely stop with such a regular filter-media cleaning as I have been doing so far.
Serratus and Mark- thanks for that, I'll definitely be looking into a second filter for the system- quite sobering to think that if I was away for a day or two I prob would have come home to a tank of quite expensive, belly-up fish!
Ian- think I already answered most of the questions you asked if you had read the thread fully. I'll go through them again for you. I washed the sponges in tank water and they were out of the tank no more than 15mins. Fish was alive when I went to work, dead when I got home, so possibly a few hours, but hard to tell. Obviously took him out as soon as I got home- didn't leave him in there to see if he'd get better if that's what you mean! I was also concerned about the ammonia, but the Nitrite was so high I thought it was imperative that I got advice on that ASAP. If that killed all my fish, wouldn't really matter what level the Ammonia was at! I believe Nitrate to Nitrite conversion is quite rare in an aerobic system (might be wrong). Nitrate is reading about 1-2ppm, nothing too high. pH is about 6.8-7, the high end of Discus tolerance, but think that's about fine. It's naturally about 7.2, but can drop it by boiling about half the water that goes in (just use any water left in kettle after making tea rather than expense of purpose boiling- surprising how quickly this builds up in two days). The water hardness is about the upper tolerance of Discus, but don't buffer, that's how it is naturally in my tap. Think I already mentioned how aften I do water changes- about 30% over the week, but done over 3-4 days to limit water fluctuations.
Again, thanks to everyone for the advice,
Lorcan.

Good to see all back on-track.

But, nitrate to nitrite conversion does happen in aerobic conditions, and in some cases nitrifying bacteria that normally convert nitrite to nitrate can reduce nitrate to nitrites under aerobic conditions.

The system is balanced to be quite dependant upon the carbon source. I won;t go into the biochemistry of it though. (you'll be glad to hear).

ian

Oh right. Thanks. Do you have any links I could read up on it? Curious about that now.

Xaribdis wrote:

Oh right. Thanks. Do you have any links I could read up on it? Curious about that now.

I don't have any links at present, but I can hunt the internet for some links; and I'm not going to write an article just yet for you.

If you want to google it then terms such as 'Nitrate Reductase' should get you somewhere.
BUT beware.....there are different types of nitrate reductases and their expression, action, and inhibition vary as well as their location within the bacterial cell.
Some are not inhibited by aerobic or anaerobic conditions, some may be inhibited by ammonium and others not.

What you really want are scientific review papers on this as I would guess that anything short of a scientific paper may be too short of anything useful.
Some of the scientific research papers will have loads of data that is as useful as a bike to a fish.

I am fortunate in that I have an account for many of the on-line papers; unless you have that you'll have to get the few that are free.

Also, it may be worth noting that nitrate reduction to nitrites is not the same as nitrate reduction to nitrogen (that is denitrification), so take care when reading to make sure you have the correct context for nitrate reduction.

You may also like to enter 'nitrobacter' in your search to see what comes up.

ian

here's a link to a free on-line paper...

mic.sgmjournals.org/cgi/reprint/143/12/3767