Nitrite Wont Go Down!

[cheekymonkey]

Hi
I've got a 30l bioorb and had it cycled for 5 weeks before putting in any fishes. Got hold 4 guppies and introduced them to the tank. The temp is around 24-25C, pH is about 7.4. I'm testing ammonia and nitrite daily and its showing zero for ammonia but the nitrite level has somehow shot up to 2ppm since the second day.
I've been carrying out daily water changes for a week now, about 1/3 of the tank, even did a 2/3 water change but it doesnt seem to be helping much. Whats causing the nitrite level to remain at that high level?? I'm only feeding the guppies once a day in small amounts.

 

[rust81]

Have you tested your tap water that you are doing the water changes with? If you water source has natural nitrites then doing a water change isnt going to help. If your water test comes back fine then i would imagine that your tank probably isnt cycled. How did you cycle the tank, and how long did you wait before adding the fish?

 

[cheekymonkey]

I did a nitrite test on my tap water already, zero nitrite from the tap. It took me 5 weeks to get the bioorb cycled, I used household ammonia from homebase, just followed the instructions on the Fishless Cycle post. I was testing ammonia and nitrite daily on the last two weeks of the cycle and the levels were returning to 0.25 for both overnight.

 

[rust81]

How long did you wait from adding your last dose of household ammonia before putting the fish in the tank? If this was longer than 8hrs AFTER the last ammonia was processed by the bacteria then it is possible that the bacteria could have started to die off.....

 

[cheekymonkey]

When I tested it, it was morning, ammonia level was like 0.25, I got the fishes in the afternoon around 4pm.

 

[mark.w.jones]

What test kit are you using?

 

[cheekymonkey]

API liquid master test kit. Just did a nitrate test as well, showing 10ppm so some nitrite is being processed but obviously not enough for whatever is causing the spike

 

[rust81]

Stupid question but did you use dechlorinator when you did your water change? Either something has killed off the bacteria in your filter or there isnt enough bacteria present to cope with the bioload (ie not cycled).

 

[cheekymonkey]

It did occur to me I might have killed off some bacteria through the 80-90% water change but yes, dechlorinator was used(stress coat) on the water before it got put into the bowl, otherwise my ammonia level would of shot up too. I've got four small guppies in the tank at the moment so I wouldnt say its causing that much strain on the bioload

 

[jennybugs]

Dechlorinator doesn't stop your ammonia levels from rising. It removes chlorine and heavy metals from the water making it safer for the fish.

It's highly likely that if you still had ammonia and nitrite readings before you added the fish that your biorb hadn't actually finished cycling.

What are your readings today?

 

[rust81]

Dechlorinator doesn't stop your ammonia levels from rising. It removes chlorine and heavy metals from the water making it safer for the fish.

The reason for me mentioning the dechlorinator is that if this hasnt been used, the chlorine in the water can kill the bacteria in the filter and therefore you end up back at square one in the cycle.....

 

[jennybugs]

Oh I know that...I was replying to Cheekymonkey's comment...

dechlorinator was used(stress coat) on the water before it got put into the bowl, otherwise my ammonia level would of shot up too.

 

[Squid]

I did a nitrite test on my tap water already, zero nitrite from the tap. It took me 5 weeks to get the bioorb cycled, I used household ammonia from homebase, just followed the instructions on the Fishless Cycle post. I was testing ammonia and nitrite daily on the last two weeks of the cycle and the levels were returning to 0.25 for both overnight.

When I tested it, it was morning, ammonia level was like 0.25, I got the fishes in the afternoon around 4pm.

I have to agree with Jenny bugs. It doesn't sound like your tank was cycled.

I'm a little confused as to why you added the fish when you were still testing positive for ammonia and nitrites?

Squid

 

[cheekymonkey]

I'm just gonna assume I built enough bacteria for ammonia BUT not enough for nitrites. Tested both again tonight, zero for ammonia but still at 2ppm for nitrites. Thanks for the advice folks, just gotta keep close eye on my guppies, still pretty active though.

 

[jennybugs]

Just keep changing that water! That'll bring the nitrites down. Nitrite is just as toxic for fish as ammonia is and needs diluting as soon as poss