Nitrate Problem ?

[chris301up]

I have had my aquarium setup for about 14/18 months and now, over the past couple of months or so, my fish, particularly Mollies, have been dying off at regular intervals.

I have done all the usual tests, but today I have found the nitrate levels very high, at between 50/100.

I have done a 50% water change, but it hasn't seemed to have made any difference.

The domestic water measures at around 10, so there is obviously a problem elsewhere. All other measurements for pH, Amonia and Nitite read as normal.

I don't want to restock the tank until I have sorted out this problem, so does anyone have any advice?

Just for information the aquarium is a Juwel Rio 180 with a standard compact internal filter and two 200w heaters. There is approximately 2 inches of substrate, a few artificial plants and no rocks or ornaments.

 

[rabbut]

How often do you normally do water changes and how much do you change each time? What are the exact numerical stats for Ammonia, Nitrite, Nitrate and pH? Can you re-test your tap water also, just to ensure the test kit isn't faulty, or the tap water levels have changed What fish do you have ATM, and how many? Do you notice anything unusual on or about the fish before you loose them, either before or after death?

All the best
Rabbut

 

[chris301up]

How often do you normally do water changes and how much do you change each time? What are the exact numerical stats for Ammonia, Nitrite, Nitrate and pH? Can you re-test your tap water also, just to ensure the test kit isn't faulty, or the tap water levels have changed What fish do you have ATM, and how many? Do you notice anything unusual on or about the fish before you loose them, either before or after death?

All the best
Rabbut

Hi

I ususally change about 20 - 25% of the water on a weekly basis.

The stats are as follows: pH = 7.5/8.0 Amonia = 0.0/0.6 Nitrite = 0.1 and Nitrate = 50/100 according to my test kit.
Domestic water tests Nitrate at 10 which is about normally for my area.

My last few fish are 1 x Otto, 1 x Tiger Barb, 2 x Dwarf Gouramis, 4 x Neon Tetras and 5 x Mollies.

The Mollies usually become narrow and find it difficult to swim and then just lie on the bottom.

Trust this helps?

 

[jmkgreen]

For a mature tank like that your Ammonia and Nitrite should never rise above nil. Do you have plants that may be rotting? How much do you feed your fish and how frequently?

When you do you water changes, do you clean the sponges in the filter? If so, with what, tank water or tap water?

 

[Curiosity101]

Agreed with the above.
Can you try to list EVERYTHING you've done ever since 1 month before fish started dying.
New fish..
New decorations..
New Plants...
New media...
New Chemicals...

ANYTHING you can think of, however small it is. In a mature set-up something must have changed to cause those results.
A tank as mature as yours should give Ammonia and Nitrites of 0. And nitrates (with your tap water) of around 30ppm.

I'd suggesting doing 2 x 50% water changes to get all your results at a slightly better level.

 

[chris301up]

For a mature tank like that your Ammonia and Nitrite should never rise above nil. Do you have plants that may be rotting? How much do you feed your fish and how frequently?

When you do you water changes, do you clean the sponges in the filter? If so, with what, tank water or tap water?

My readings for Amonia and Nitrite have always read about the same as quoted.

I usually feed the fish once a day with just enough for them to eat within about 1/2 minutes.

I have artificial plants and do regular water changes about 7/10 days or so.

I never clean the all the filter media at the same time. I usualy clean one sponge at a time, using water taken from the tank, working my way down from the top.

Have done another test today and it reads the same, so will do another water change and see what happens?

 

[Curiosity101]

Then your tank has never fully cycled by the sounds of it...

You really should do as many changes as it takes to get nitrates down to 40 or below.
Ammonia needs to be kept below 0.25, as does Nitrites.

I would up your water change routine to 20% every week.
Other than that everything sounds ok...

What is your stocking? Only thing I can possibly think is that your filter can't cope with the number of fish.

 

[chris301up]

Then your tank has never fully cycled by the sounds of it...

You really should do as many changes as it takes to get nitrates down to 40 or below.
Ammonia needs to be kept below 0.25, as does Nitrites.

I would up your water change routine to 20% every week.
Other than that everything sounds ok...

What is your stocking? Only thing I can possibly think is that your filter can't cope with the number of fish.

As mentioned in my previous post my current stock is down to 1 x Otto, 1 x Tiger Barb, 2 x Dwarf Gouramis, 4 x Neon Tetras and 5 x Mollies.

I have now done another water change but I have always been a little suspicious of the internal filter setup designed by Juwel. No doubt it works fine, but I am currently thinking about trying an external filter such as a Fluval 204 or similar, if I can get one at the right price.

I don't want to spend a fortune on another filter if it doesn't work and really only want to give this a go to see if it cures the problem?

In the meantime I am going to give the tank a few days to settle down again, then take some more readings and go from there.

 

[arobinson1984]

Is there any ammonia or nitrite reading in your tap water?

I'd recommend upping your weekly changes to 50% a week once everything has settled, in the meantime you will have to do water changes whenever the ammonia or nitrite rise above 0.25ppm

Andy

 

[rabbut]

If those results are normal though for you and your tank, and they are low-ish readings, is it not possible that the test kit is at fault? How old is the kit, when is it's use by date, what brand is it and what form-factor (strips, liquid drops, tablets, powder e.t.c)? Also, how do you store it? Also, can you get the water tested at an LFS, and compair their kits results to yours. Don't forget to get the numerical results, don't accept "it's fine", as it often isn't when they say that

Smaller external filters are equally as good as the Juwel internal IME. I used to run a Juwel Record 96 at about 5" per gallon with the Juwel internal only, and it coped perfectly fine They take some abuse, but are good from a biological and mechanical filtration point of view. Reliability has become an issue recently though after Juwel moved production to China...

All the best
Rabbut

 

[chris301up]

If those results are normal though for you and your tank, and they are low-ish readings, is it not possible that the test kit is at fault? How old is the kit, when is it's use by date, what brand is it and what form-factor (strips, liquid drops, tablets, powder e.t.c)? Also, how do you store it? Also, can you get the water tested at an LFS, and compair their kits results to yours. Don't forget to get the numerical results, don't accept "it's fine", as it often isn't when they say that

Smaller external filters are equally as good as the Juwel internal IME. I used to run a Juwel Record 96 at about 5" per gallon with the Juwel internal only, and it coped perfectly fine They take some abuse, but are good from a biological and mechanical filtration point of view. Reliability has become an issue recently though after Juwel moved production to China...

All the best
Rabbut

The test kit is a few weeks old and it is a Hagen Essential Mini Kit for all four tests with a use by date of 30th October 2011.

Its form factor is liquid drops with colour charts and it is stored in the cabinet under the aquarium which is normally cool.

I have had the water tested in the past by my LFS which proved to be similar to the readings taken by me, so I obviously have not used them since purchasing my own test kits. I will have to give them another go?

 

[chris301up]

Agreed with the above.
Can you try to list EVERYTHING you've done ever since 1 month before fish started dying.
New fish..
New decorations..
New Plants...
New media...
New Chemicals...

ANYTHING you can think of, however small it is. In a mature set-up something must have changed to cause those results.
A tank as mature as yours should give Ammonia and Nitrites of 0. And nitrates (with your tap water) of around 30ppm.

I'd suggesting doing 2 x 50% water changes to get all your results at a slightly better level.

I can't remember anything any different as I havn't changed the tank setup except for adding another heater.

I have checked back through my notes from when I do tests and my stats are always very similar as follows:

ph = 7.5/8.0 (Ave)
Amonia = 0.0/0.6 (Ave)
Nitrite = 0.0/0.1 (Ave)
Nitrate = 0.5/0.10 (Ave)

I took samples from the domestic supply last night and all was fine, but I will say however, that after leaving the water to dechlorinate for a few hours the Nitrate level has risen from a negligable level to about 0.10? I am going to leave this water for a few more hours, and before adding it i will take another sample?

I am also thinking of cycling the tank again. Maybe adding a Biological Aquarium Supplement?

Any comments.

 

[chris301up]

Agreed with the above.
Can you try to list EVERYTHING you've done ever since 1 month before fish started dying.
New fish..
New decorations..
New Plants...
New media...
New Chemicals...

ANYTHING you can think of, however small it is. In a mature set-up something must have changed to cause those results.
A tank as mature as yours should give Ammonia and Nitrites of 0. And nitrates (with your tap water) of around 30ppm.

I'd suggesting doing 2 x 50% water changes to get all your results at a slightly better level.

I can't remember anything any different as I havn't changed the tank setup except for adding another heater.

I have checked back through my notes from when I do tests and my stats are always very similar as follows:

ph = 7.5/8.0 (Ave)
Amonia = 0.0/0.6 (Ave)
Nitrite = 0.0/0.1 (Ave)
Nitrate = 0.5/0.10 (Ave)

I took samples from the domestic supply last night and all was fine, but I will say however, that after leaving the water to dechlorinate for a few hours the Nitrate level has risen from a negligable level to about 0.10? I am going to leave this water for a few more hours, and before adding it i will take another sample?

I am also thinking of cycling the tank again. Maybe adding a Biological Aquarium Supplement?

Any comments.

Just an update.

I have now left the aquarium to settle and have added a Fluval 204 filter which has only been running for about a day.

I have done a 50% water change and taken another sample but the nitrate level hasn't changed yet.

My LFS has advised that I also stop feeding for about a week to see if this will help?

 

[rabbut]

Personally, with consistant readings like that, unless you are overstocked, I'd put it down to the test kit Hobby level test kits can only really give a ball-park figure, they aren't always accurate What kit do you use?

 

[chris301up]

Personally, with consistant readings like that, unless you are overstocked, I'd put it down to the test kit Hobby level test kits can only really give a ball-park figure, they aren't always accurate What kit do you use?

As I mentioned in a previous post I use a Hagen Essential Mini Kit.

The readings have been quite normal before, so even if they give a 'Ball-Park' figure, I would assme that there is still something wrong?

I am going to leave the two filters working for a coupke of week and then remove the Juwel unit and then see if this makes any difference in due course.