Getting Rid Of Nitrites

[7755matt]

We have a fry tank set up for our new hatch of ancistrus.

I've been away this week but my wife rang the other day to say the nitrite levels were through the roof.

I suggested water changes so she did 3x 50% water changes in a day and tested the water each time. It didint drop the level very much

We thought we'd put our new fluval U3 in with a whole pot of bactinette live bacteria (as suggested by the LFS). That didnt have much effect. We've now removed the old plus2 that was in there.

We've just done another 50% water change and its still wont seem to drop below 1.

Tap water has been tested and its fine, all our other tanks are showing 0

Any suggestions as to what the problem is, cure and so on.

Its a 50 litre hexagonal plastic/acrylic tank. small piece of bogwood and a new plant (amazon sword added this evening). Approx 30 ancistrus fry.

we lost at least 10 fry when the level spiked, and now we cant get the level down very far, I dont want to lose any more

 

[WILDER]

Just tank a sponge from a mature tank and add it to the filter.

 

[7755matt]

Sorry i forgot to say that i had sponge from a mature filter put into the plus2 when the tank was set up, along with a good dose of 'cycle' - i know there's a big debte as to how good it is but we added some anyway.

 

[WILDER]

The only cycle product thats any good is bio spira.
Nutrafin cycle might as well throw it in the bin.

When you added the mature sponge was the fry tank the same temp as the other tank that you took the sponge from.
As if temp lower you can lose some beneifcal bacteria.

 

[7755matt]

it was maybe 1-2 degrees warmer of anything.

we reckon we've put 80 litres of fresh water through the tank in the last 3 days and its still high

 

[WILDER]

How long has the tank been set up now.
I would maybe squeeze some beneifcal bacteria onto the sponges from the other tanks you have.

I don't know anything about the fry you keep.
Can you put them in the main tank if there plenty of hiding spaces.