Nitrate never get to zero

[Mike220]

hello evey one
I have 20 galon quarantine tank.
I started cycle from October, 2016 and all parameters is good after 2 months. Then I quarantine 2 fishes for 4 weeks than put them in display tank.
Then after 2 weeks I quarantine another 2 fishes. First 2 weeks is ok, and in the morning and went down to basement and see fishes look bad. I check water and OMG my nitrate went up to 90 ppm (test turn red color ) I did not feed too much. I really don't know why nitrate went up. Do water change every week. Anyway my fishes are dead.

So, beginning one January I did change 10 to 20% water every 2 weeks, nitrate went down to 15ppm.
And never put fish back to quarantine again, but nitrate never get lower than 15 ppm.
So far already 4 months with no fish.
Can you guys tell me why , my nitrate went up so quickly and never get to zero again.

Thanks

 

[rockhead51]

What else is in there? Filter? What kind? Any media at all?

 

[Griff]

How did you prepare your rock. My nitrates skyrocketed after about a 1.5 months as all the dead material broke down into the water column. I used a biopellet reactor and it brought them down to zero after 2 months. The issue was I had a major phosphate issue still. I used phosphate rx but didn't know I needed a 5 micron filter sock. I was then plagued with phosphates leaching back into my system. A year later finally things started to balance out. I will never use uncured rock again.

 

[Mike220]

I used marineland penguin power filter 50 and have 2 live rock.

 

[Mike220]

2 live rock from. My display tank

 

[Zack K]

Your fish did not die from the nitrate. I have 160ppm Nitrate in my DT at the moment and I have flourishing GSP, Kenya Leathers, Frogspawn, I had 5 chromis, Longnose Butterfly, blennies, all happy and healthy. I no longer have the fish due to a Velvet outbreak but Coral is happy and healthy. I recently started running BioPellets and well, I'm still waiting for the nitrates to drop. I would recommend BioPellets to you if you want 0 Nitrate but that isn't necessarily good. A reef needs some Nitrate to survive. As for the fish deaths, their is something else that happened.

 

[Mike220]

This is my quarantine tank not a display tank
My display tank is 3ppm nitrate

 

[Pmj]

You're not going to see nitrate dropping very much with 2 rocks & a HOB filter.

 

[phillygeeks]

Fish tolerate relatively high nitrates, so I doubt that was what killed them. Explaining why your nitrates are not decreasing probably requires more investigation. Look into what sources of nitrate production you have and look into trying a different test kit from whatever you are using

 

[Mike220]

I have 2 test kits
Red Sea and salifert

 

[phillygeeks]

If the tests correlate then you can probably rule that out. Next question is are you doing any further water changes to decrease your nitrates after they hit 15ppm and how much time has elapsed since it hit that level and remained steady (as I understand, bioogical mechanisms are typically not as robust naturally to eliminate nitrate e.g. to nitrogen gas, in a lot of systems)? Another helpful bit of info as I'm sure will be asked is what were the water parameters? Did you measure and trend ammonia and nitrite in the QT? Also, what is your source of water and are you measuring TDS?

 

[40B Knasty]

Looking at a few things here possible.
1)Where ever you got them from. What was the salinity compared to yours? Some places run really low like 1.018 to dodge illnesses and if you have 1.026. That's really hard on a fish. More salt less O². It would take weeks to raise it up safely from that.
2)Stray voltage.
3)Ammonia
4)Disease like velvet
You never mentioned what kind of fish. So if you have 2 fish, that don't pair well, in a 20g tank, and with no separation or cover they desire.
You should also mention what kind of media.
Also after the first fish were put in the DT. Did you put the 2 rock back in also to the DT and then add those 2 rocks back to the QT after two weeks when you picked up the 2 dead fish for the QT?

 

[Mike220]

If the tests correlate then you can probably rule that out. Next question is are you doing any further water changes to decrease your nitrates after they hit 15ppm and how much time has elapsed since it hit that level and remained steady (as I understand, bioogical mechanisms are typically not as robust naturally to eliminate nitrate e.g. to nitrogen gas, in a lot of systems)? Another helpful bit of info as I'm sure will be asked is what were the water parameters? Did you measure and trend ammonia and nitrite in the QT? Also, what is your source of water and are you measuring TDS?

Ammonia and nitrite is zero
And TDS is 1 and I use ro/di water same with my display tank. My display tank hit zero nitrate. I have to dose nitrate to get it up to 3 ppm

 

[Mike220]

Looking at a few things here possible.
1)Where ever you got them from. What was the salinity compared to yours? Some places run really low like 1.018 to dodge illnesses and if you have 1.026. That's really hard on a fish. More salt less O². It would take weeks to raise it up safely from that.
2)Stray voltage.
3)Ammonia
4)Disease like velvet
You never mentioned what kind of fish. So if you have 2 fish, that don't pair well, in a 20g tank, and with no separation or cover they desire.
You should also mention what kind of media.
Also after the first fish were put in the DT. Did you put the 2 rock back in also to the DT and then add those 2 rocks back to the QT after two weeks when you picked up the 2 dead fish for the QT?

No , 2 live rock from I start do cycle the quarantine tank, never take it out.
1 power blue tang and one anthias. They never fight and it like pig in 2 weeks. No axtra media only filter with a little carbon inside

 

[40B Knasty]

Okay. I really did not get what you meant on some of the sentences.
First thing you will hear is. "Tangs are hard to get as a healthy fish." They are bad for fluke, velvet, and ich. I would agree since I see so many people say they have nothing but problems with them.
Next I would say you might have starved out your good bacteria with no ammonia in the QT for 2 weeks with no media to hold it and only 2 rocks. Carbon bags are only good for 4-6 weeks from what they say. Think about this first. People use 10x as much carbon in a reactor and they change that out every week. After knowing what people do with 10x as much. I will say more like 2 days for tiny bag.

 

[Zack K]

This is my quarantine tank not a display tank
My display tank is 3ppm nitrate

If this is only your QT tank do a 100% Water change. Problem solved.

As for why the fish died. A powder blue tang and anthias are two very difficult fish to keep. As one mentioned above the PB are very susceptible to disease such as Velvet, Flukes, Ich, and bacterial infection. The anthias could have taken a shot from the salinity swing or also had Velvet. If you were just observing them I would say their was an Ammonia spike after you put the fish in because the biological load was more than your bacteria could handle initially.
Do you have an Ammonia badge in your QT
Were these your first 2 fish

Let's see if @Humblefish has any suggestions on to why these guys past on.

 

[Water Dog]

I used marineland penguin power filter 50 and have 2 live rock.

As to the nitrate issue, my guess is that you're nitrates are super high because of your power filter. If I'm not mistaken, the Pengiun power filter uses biowheels, correct? The biowheels are super efficient at booting nitrates IMO. Get rid of the biowheels and the nitrates should go down and stay down with water changes.

 

[Mike220]

As to the nitrate issue, my guess is that you're nitrates are super high because of your power filter. If I'm not mistaken, the Pengiun power filter uses biowheels, correct? The biowheels are super efficient at booting nitrates IMO. Get rid of the biowheels and the nitrates should go down and stay down with water changes.

You mean take bio wheels out ?

 

[Water Dog]

Yup, my understanding is that it is the same reason we no longer use bioballs in our systems. The biowheels are very efficient at providing an aerobic surface area for bacteria to grow to break down waste. That aerobic bacteria is nitrates that will build up in our systems over time if not removed aggressively through water changes.

 

[phillygeeks]

+1 on removing the biowheels. Seems like you have most else covered