Very high nitrates!?

[Shane87]

It's not my tank it's my sisters but I help her with it a lot, she changed her tank about a week ago and some of her fish have been dying so I just told her to do a PWC until I could test it today, anyways everything was fine on the API masters kit except nitrAtes and they was sky high, I have never come across this before.
Amo 0

rItes 0

RAtes 80ppm+
Temp 27.

 

[FeldmansFish]

What is the tank size and gph on the filter? I'd recommend more water changes maybe 50%ish.

 

[Shane87]

It's a 35 litre and its got a hob filter, not sure what 1 but its rated for 50 litre or bigger from what I remember and yea I said the same about water changes and she said she had done about a 60% yesterday and the nitrates are this high today! I just don't get it...

 

[Rivercats]

Nitrates can also come from tap water, you should test the tap water being used in the tank because if it has high nitrates you'll never get them down. Also if a filter gets really dirty it will increase nitrates.

 

[Mumma.of.two]

Was the same substrate used?
When you say changed, do you mean redecorated or switched to a different tank?

 

[Shane87]

Ok thanks, never thought to check the tap water but I know about the filter and the filter floss was changed 2 days ago and the bb media looks clean so I don't think that is the problem

 

[Shane87]

Yea she used the same substrate out of her previous tank, and ammonia and nitrite are fine so couldn't be a cycling issue could it?

 

[stingrays4]

Hi first thing is to check your test kit. This is easy just check either your own tank or the tap water and see if the readings vary or not?
If the test kit is reliable,then you need to give the tank a good clean,using a gravel syphon and remove as much muck as possible,from the gravel around plants etc. Also from inside the HOB. Also cut down the feeding by 50% this should then reduce the nitrates over time.

 

[Shane87]

Ok I will tell her to try that, she normally gives it a good vac when she does a PWC but I will tell her to do it again, the test kit is Defo fine I done the weekly tests on my tanks yesterday and all was fine, only new thing in the tank is an old piece of drift wood that was from her friends tank, could it be that?

 

[stingrays4]

Hi possibly but unlikely? have you checked the tap water for nitrates? It sounds like a classic case of overfeeding? Fish require surprisingly little food.
If the tank looks clean then it probably is. If you stir a little area of the gravel or sand or what ever the substrate is,it should raise a little 'muck' but not too much and it should be a brownish colour?

 

[Mumma.of.two]

My first thought was excess waste being kicked up from under the gravel during the move. Whatever the cause, a good number of PWC should do the job.

 

[Shane87]

No I can't check the tap until tomorrow because I don't live there and yea I stirred it up a little and it was a little dirty but not as bad as I would expect for them levels :/ it's really got me stumped, i have had aquariums for years and never seen this happen.