Nitrates High In Malawi Tank

[Go_fish]

All other levels are fine, but my nitrate is running high and I want to get it down. Can I do water changes every day, or is every other day better? Planning on about 60 - 70 litres each change. Not sure why they have gone up so fast - added new fish 4 days ago and am running 2 well-established external Eheim cannister filters (one as bio, 1 as mechanical). Ammonia is nil and nitrites are negligible.

Please advise

Thanks in advance

 

[jgray152]

Nitrates will always increase as the Ammonia and Nitrites decrease. There is no stopping it with filtration. water changes are the only way to remove it. I would do 25% every week. Every day may be to stressfull for the fish.

 

[Go_fish]

Nitrates will always increase as the Ammonia and Nitrites decrease. There is no stopping it with filtration. water changes are the only way to remove it. I would do 25% every week. Every day may be to stressfull for the fish.

thanks for the reply jgray152 - all the fish seem absolutley fine, so hopefully all will be ok. By doing 25% a week, it will take quite some time for the nitrates to go down - is this ok for the fish?

 

[Nick Sw]

What is "High" , how much ?
What is your water chage routine at present ?

 

[Go_fish]

What is "High" , how much ?
What is your water chage routine at present ?

Reading about 80 at the moment. Prior to changing the tank to Malawi, it was running as a community tank, but with low stock (4 clown loaches, 3 red-tail sharks, 6 zebra danios, 1 bn, and 1 firemouth) so was doing about 10% every 2 weeks and this was absolutley fine. 2 external eheim cannisters running - one as a bio, and 1 as a mech (with phoszorb, nitrazorb and clearwater pouches). Filters last cleaned (with tank water) 3 weeks ago at the same time as changing the gravel to crushed coral gravel, and adding the ocean rock (approx 50kg). Added the 12 small cichlids last Sunday, and now the nitrates have risen ++. Tap water reading is about 20-40.

thanks

 

[Druchii]

when cleaning the filteres, did you remove alot of the bacteria (accidently) and now it is spiking??

nitrates around 80-100 will harm the fish in the long run, you should be aiming to do 25% weekly water changes, no need for more than that as long as your not to heavily stocked and you appear to have plently of filtration..

with a tap reading of 40 you'll only ever dilute it, so say 75% tank is 80ppm and 25% of new water is 40ppm you'll only be diluting it down to 70ppm unless you use other things as well like mentioned.

have you left the tap water to settle and tested 24hours later to see what the result is??

 

[Nick Sw]

Like Druchi has said aim for 25% water change every week or twice weekly maybe even larger water changes (40-50%) once a week.
If your getting High Nitrates then your biological filtration is working well enough as Nitrates are the end product, the NitrIte is a slight concern maybe thats just because you`ve added more fish but keep an eye on it it should be 0.

I would maybe watch how much your feeding your fish it could be too much, Mbuna will always appear hungry.
Do you think you could be over feeding ?

Which test kits are you using ? Try to follow the instructions to the letter.

You could try a Nitrate absorbing resin such as Purigen in your filter and see how it goes.

 

[Go_fish]

when cleaning the filteres, did you remove alot of the bacteria (accidently) and now it is spiking??

Definitely not - i only ever clean the filter and sponges with tank water

have you left the tap water to settle and tested 24hours later to see what the result is??

No, not done this but will do

Thanks

I would maybe watch how much your feeding your fish it could be too much, Mbuna will always appear hungry.
Do you think you could be over feeding ?

When it was running as a community set-up I used to feed the tank once every 2 days, but since adding the cichlids, the LFS told me to feed them once or twice every day - algae flakes. I have been feeding them once a day, and only as much as they will eat in 3-4 mins. Do you think I should go back to every other day? Will this raise agression levels??

Which test kits are you using ? Try to follow the instructions to the letter.

Haagen test kit - about £60 and contains tests for pretty much everything! Liquid stuff rather than the crushed tablet form. Am following instructions exactly.

You could try a Nitrate absorbing resin such as Purigen in your filter and see how it goes.

The external Eheim that I am using as a mechanical filter has a phoszorb, nitrazorb and clearwater pouch in it already. Am going to add a second nitrazorb pouch.

Have you heard of Tetra's 'Easy Balance?' and if so, any comments? It claims to be able to reduce the nitrate level by adding it weekly.

Cheers

 

[Nick Sw]

I think as much as they can eat in 3-4 mins is definitely too much, I`d try feeding once a day and as much as they eat in 1 or 2 mins at most.
They will always appear hungry.

 

[adambrum]

I think you will get higher readings with a higher ph aswell but im not 100% im sure nick will explain it better.

 

[Nick Sw]

I think you will get higher readings with a higher ph aswell but im not 100% im sure nick will explain it better.

No thats not correct.
Nitrate is measured in PPM by your test kit (parts per million) so what ever the PH it`s always going to have the same levels of Nitrate.

I think your getting crossed with - Ammonia being MORE Toxic at higher PH levels as the pH increases, the percentage of un-ionized ammonia (the toxic form) also increases.

 

[Go_fish]

Thanks for the feedback guys - I will cut the feeding down (still onle once a day, but will use less food).

Hopefully the nitrates will keep going down

 

[Nick Sw]

It`s a pain your Tap water is so high in Nitrate it`s almost criminal.
You can use an inline Nitrate remover when doing water changes so the water going into the tank has nitrate removed . If you feel you are losing the battle.

 

[Go_fish]

It`s a pain your Tap water is so high in Nitrate it`s almost criminal.
You can use an inline Nitrate remover when doing water changes so the water going into the tank has nitrate removed . If you feel you are losing the battle.

I know - I feel like I am fighting a losing battle to some degree as the nitrates in the tap water are so high

I think I will really have to try to use some sort of chemical to remove it as I don't think water changes alone are ever going to do the trick