Ongoing nitrate problem

[ineke]

I am still having problems with my TB/Mischling tank in relation to nitrates. They have remained high for 12 months - high being around 20 . The tank is a 24 " with benibachi soil, mosses, a bit of driftwood, some water sprite. It is RO water with GH+, 2 sponge filters and an Eheim 2213 canister which has 3 sponges, seachem matrix and glass noodles. Water parameters TDS 150 PH 6 KH 1 GH 5 Ammonia 0 Nitrites 0 Nitrates 20 but presently 40 after no water changes for 7 weeks . Normal weekly maintainence is 10-15% water change with RO and minerals.

All my other tanks have a nitrate of 0 - 5 and this tank has always been higher despite being fed and treated the same as the other tanks. The only difference seems to be the canister so I'm thinking the filter media is causing the problem. I am quite happy to replace all or part of the media but would appreciate some input as to what may be the problem media- so I don't buy the same- and how do I then reintroduce the canister with new media to an established tank. Alternatively I could just remove the canister but this would be a last resort.

I have tried water changes over a period of a week but it seems to make little difference . The shrimp are breeding but the shrimplet survival rates are not as high as they should be.

Any ideas guys

[OzShrimp]

I use seachem matrix and never had a problem, never used glass noodles so cant say. Have you checked inside your canister to see if you have any waste or dead shrimp in there which may be causing it ?

 

Do you dose beneficial bacteria like seachem stability when you do you water changes, if not it could be dieing off and not regenerating in time.

 

I honestly couldnt see the matrix being the problem so wouldnt really remove that personally, if you replace the noodles put the replacement in with the already established matrix and same goes for if you have some spare established media in you other filters you could also add some of that whilst the new stuff re establishes itself

[ineke]

I find it strange that the nitrates stay high but the ammonia and nitrites are 0. I haven't used beneficial bacteria for a while but I would have thought the tanks with the sponge filters would have a problem before the canister filter tank. I did check the canister today and no dead shrimp etc in there. There was a bit of dirt from the soil but nothing major.. I have had trouble with this canister from the beginning- it took nearly 3 months for the tank to cycle - this was my 30" tank that was setup new with new filter and new soil- I eventually had to change to the smaller tank when I setup my shrimp room but used the same soil and water to set it up. The tank has been setup since last December. I really am at a loss as I think the nitrates may have been higher than 40 I took the reading after a water change. I did it again to check it was right . I am using all the same type of media in another canister - my 200 litre tank- with no problems. I'm very tempted to take the canister out of the loop but that still won't give me a cause and I'd like to know what is causing it.

[CNgo2006]

Maybe add some purigen/macropore or other nitrate media (nitrazorb, etc), consider adding more live plants, Keep doing small wc until it is down to <5...what media are you using atm? And what filter is it?

Edited August 26, 2014 by CNgo2006

[ineke]

Hi Chi I listed the filter and media in the original post - Eheim 2213 with seachem matrix, noodles and sponges.

I am just recharging my purigen and will put that into a power filter . I will buy some nitrate removing sponge tomorrow to put in the power filter as well. What I really want to find out is why only this tank is having a problem. As this is the only tank I have an Eheim canister on it must be something to do with the canister and the filter media.

[petfish]

Nitrate is caused by excess waste, eg:food, organic waste, rotting plants etc etc, I would clean out canister and replace the noodles with marine pure spheres as they help to reduce nitrate, also I would do 30-40 percent w/c each day till nitrates are where you want them.

[ineke]

Thanks- this tank is pretty clean with little organic matter laying around and to make absolutely certain there is no debris I ran a power filter for 3 days, the canister has been cleaned , water changes have been done. This is an ongoing issue from when the canister was new. I replaced half the media to seachem matrix about 6 months ago but the problem persists. I'm thinking now it must be either the noodles or the sponge. I might just take the canister off the tank and run the power filter with the purigen and nitrate removing sponge for a few days.

I have spare noodles I can put into the canister so I might take some of the sponge out of the canister and try the canister on a different tank that is low nitrate to see how it goes. It just baffles me why only this tank has a problem. If it was my feeding or my maintainence then all my tanks would surely have a problem.

I have berried females in this tank and as it has been very stable with no water changes for 7 weeks the 30-40 % water changes would be too drastic just now - it may cause the females to molt and therefore lose their eggs. I have been doing small water changes daily with water warmed to match the tank temperature but only a couple of litres a day for this last week since I've been home. It has made only a small change in the nitrate level

Edited August 26, 2014 by ineke

[OzShrimp]

do you gravel vac your soil when you do your wc? i used to have issues with breeding and shrimplets and i never grael vacced my shrimp soil too often now i am pedantic and was amazed at the crap which i got out lol

[jayc]

Having some Nitrates is normal in a tank.

Ammonia is converted to Nitrite, and then Nitrite is converted to Nitrates.

Different strains of beneficial bacteria do this.

Nothing will convert Nitrates however, so this builds up.

Having some aquatic plants will help, as they use Nitrates as a food source.

But it's normal for Nitrates to climb when a water change has not been performed for a while.

Adding more filter noodles won't help, as that will only provide more surface area for the bacteria that breakdown ammonia and nitrites.

 

Removal of Nitrates will always be via the good ole fashion water change, or purigen/macropore media as a chemical absorbent.

 

Nitrate sources will be from food, which you are constantly adding, waste from shrimp/fish, decaying organic matter (dead fish/shrimp or vegetation). You could give the substrate a light vacuum. Just the top 1cm say. 

Edited August 26, 2014 by jayc

[BlueBolts]

All my tanks have eheim canisters...there's always some nitrates present...nitrates are produce via shrimp food/poo....how often do you clean your canisters ? I clean them every 1-3 months, and replace the macropore/purigen on each clean. I also carefully vacuum my substrate every now and then....

[ineke]

I don't normally vacuum the gravel as such but use an airline to pick up mulm, left over food and dead plants. I do have a reasonable number of java ferns as well as the moss and water sprite.

BB I clean the canister 2-3 monthly and regularly run the power filter with filter wool and purigen in it to pick up any loose debris. I wasn't too worried about the nitrates being 20 but when I saw 40 after a water change - meaning it was probably higher prior to the water change- I just thought I would put it out there incase anyone had an idea that might work better than what I'm doing just now. I know it's not the water I'm introducing as that is 0 and the other tanks are being treated exactly the same . It has to be something to do with the filter I can't see that it is anything else . I will soldier on doing small water changes until the babies hatch then I can do some bigger changes and I will consider what to do about the filter media. Apart from the high reading of nitrate the filter is keeping the tank crystal clear and I'm very happy with it. I just thought it might be the sponge that came with the filter or the noodles I'm using but I don't know what brand they were.

[jayc]

Nah, mosses and Java Ferns are too slow in growth rates to really eat up much nitrates.

Water change is your friend. 

[ineke]

Looks like its a day of catching shrimp and doing a big water change then reacclimatise them:( still a bit dubious about the filter but will see what happens after the water change. I really didn't want to do a big one until the babies are hatched but I don't know how long the mums have been berried.

[smicko]

Have you tried testing the water your using for waterchanges? The main problem with low ph tanks is its hard to get beneficial bacteria to grow as ammonia isn't present in water under 6.

Does your test kit go lower than 6 on the ph reading as it may be really low, i have a tank that runs at 5ph amd that took months to cycle even with bottled bacteria.

It is strange that watersprite isn't removing it. The next thing I would do is add some duckweed, i know it doesn't look the greatest but it's a great nitrate farmer

farmer and will lower them whilst you work out the issue.

Cheers mick

[FishBeast]

How many shrimp do you have in your tank? If it heavily stocked it may be that being a small tank you have heaps of bacteria in it and is converting the ammonia quickly.

 

My thoughts are that it has something to do with your substrate. You said that it was re-used? Which Benibachi is it?  Is it the plant growth one? Perhaps being used before it is leaching ammonia or nitrates into the water? Maybe it has organic material from the previous tank? 

[ineke]

Hi Guys

First the ph is about 6 now by my test kit and my ph pen which does go to 4

The soil is the Benibachi fulvic grain shrimp soil it is about 12 months old maybe a bit older but still working well. I have some of the soil from the same batch in other tanks and they are fine. I had a lot of soil in the original setup so used it in several of my new 24" tanks.

The tank is not overloaded it usually has 20  shrimp at most and I take out any extras.

I have only got a small amount of water sprite and it is only a new addition for the tank because of the high reading.

I should get some duckweed or frogbit but don't know anyone with it at the moment.I will try to source some as I don't mind the frog bit it looks quite nice- don't like the duckweed as much but know it works well

The water is used in all my tanks -I have 11 tanks and no other tank has a problem they are all 5 or less.

I still think it must be something in the canister because the other tanks are all fine and I had this problem with the 30" tank that the canister originally was setup for. It must be either the sponge that came with the canister or the glass noodles. I will slowly change these out of the system and see if that makes a difference but in the mean time I will catch my shrimp and do a big water change today then put them back in .

I can't think of anything else to do as most of you think a big water change is the only way to fix the problem- I know it will in the short term as I have done this a few times but the nitrates slowly climb back up.

All the filter media was new but as it was 12 months ago or so that I bought the canister I can't remember which type of noodles I got. I will replace them with marine pure spheres and see what happens I will just change some each time i do a filter clean up so I don't cause any spikes. Either that or just remove the canister all together the other tanks hold steady without one so that would be the easy way out!

[smicko]

Cannisters suck the oxygen from the water and bacteria need oxygen to survive so there may not be much beneficial bacteria in the cannister.

I use sponge, noodles and matrix in a wet/dry sump and have no issues so I can't see them being the problem.

When you clean the cannister do you use water from the tank?

Cheers mick

Edited August 27, 2014 by smicko

[Sprae]

Ineke, so the main problem was low shrimplet survival rates? If so, it might be other issues rather than nitrates.

 

I used to cleaned my canister filter once every 6 months, after reading this I'll do it every 3 months now. Plus I never gravel vac my soil either as there's always too much fine soil/gravel being removed with it. Either case my shrimps are still breeding so something is going ok.

[ineke]

Hi Sprae

the survival rate is not as good as it should be but the main issue is the excessive nitrates in the tank especially when all my other tanks that get the same food, water maintenance and they all sit at 5 or under.

Mick the canister is always cleaned with tank water- I wait until I am do a water change and use that water.

 

Anyhoo  I have now done what I was going to do!!! I have taken the canister off this tank and transferred it to my cull tank that at present is sitting on 5 (nitrate) and the tank with the problem has the power filter running with a special nitrate removing filter pad in it. I  decided to do a 25% water change -I warmed the water to the tank temp and adjusted the minerals to the tank and slowly changed the water - I was going to catch out the shrimp but thought it would be too stressful for the girls and as I don't know when they are due to hatch their eggs this was the best way to do it.

So now i will do a water test tomorrow on both tanks. If my thinking is right the nitrate in the canister tank should have risen somewhat overnight- it usually takes a while for it to get up to the 20 range and the TB tank should slowly start to go down.

If it is the canister then I think it must be the glass noodles I'm using -I am just grasping at straws here but we will see how things turn out. At least now I can just continue to do water changes in my TB tank until I am happy with the reading and then see if it starts to creep up again. If it does go up I will have to do a complete new setup in that tank , new soil etc. Luckily I do have a spare tank with ideal TB conditions that I could put my shrimp into -at the moment it just houses a few young CRS and some cherries -I didn't want to change the tank because I had the canister which I bought for the TBs but now it doesn't really matter where they go.

I will let you know how it works out -it might take a few more water changes before I get the results.   

[Squiggle]

After reading the whole thread it could be a couple of things I can think of straight off. Sintered glass media should always have about 50-75% replaced every 12mths(I think Matrix too) as the media gets "full" for want of a better term. As sintered glass is very porous the bacteria grows inside the media as well & isn't very easy to clean, whereas, something like ceramic noodles is mainly surface area & therefore a lot easier for the media to be cleaned & allow room for new bacteria to grow & colonize. I have always washed one of the three trays of media & all the sponges in my canister in pure tap water & replace the filter wool for this reason, this way your bacterial culture has room to grow & any die off from the culture reaching critical mass isn't a big problem. As the media is getting old & full, when any old bacteria dies off there will be an increased amount of ammonia & therefore an increase of nitrate production by the aerobic bacteria, in marine they call this a nitrate factory & this is why a more natural style of filtration(live rock, anaerobic cavity, Berlin style, etc) to remove nitrates is favoured for coral reef tanks as they require a low nitrate level, not quite as low as shrimp but much lower than fish(<10ppm)

Another thing that might have happened is when you moved the substrate on a very mature tank there would have been a large bacterial culture in your substrate &, depending on if you used the 2/3 normal to 1/3 powder top layer setup, you would have had a large anaerobic bacterial culture(not as big if you had just normal), this bacteria thrives in low oxygen areas of substrates & slowly feeds on nitrates, thereby, keeping your nitrate levels low. When you moved the substrate most of this bacteria would now be in a high oxygen environment & would have died off causing your substrate to slowly release ammonia as the organic matter(bacteria) decays & again causing an increased production of nitrates by the normal aerobic bacteria(not sure how long it would last after resetting the tank though)

I'll keep thinking about it & see I can think of any other possible reasons but for now they processes you are doing to rectify the problem are definitely on the right track.

[ineke]

Thanks Squiggs. That sounds more logical. I have ordered marine pure spheres and I'm pretty sure the noodles are the glass ones so I will replace the noodles with the marine pure. Meanwhile I will continue water changes and running the power filter and monitor the nitrate levels. I will also monitor the cull tank with the canister on it and see what happens to the nitrate levels in there.

I was very proud of getting all my tanks into a safe nitrate zone after all the over feeding I had been doing and was very perplexed by this one tank.

I hope my girls don't molt but as I am warming the water and adding minerals to equal the tank parameters I'm hopeful they will hold. My BlueBolt TBM must be near the end of her time as the eggs are now very dark - she is a beautiful colour now she is berried I hope she stays dark !

[Squiggle]

Good to hear, they usually get dark when they are preggers, they looks radiant, lol. IME the usually lighten again after but will colour up again when next berried.

[ineke]

This is her first batch and she looks to be holding quite a few. I'm slowly getting all the males out but there are still a few in the tank. I only have 1 pure TB male and hope its him that has been with the girls. I think the others are still a bit young but its time to invest in a few more pure TB's me thinks. I still haven't introduced any red into the Mischlings so that may be on the cards too.