Question: Nitrites persist at about .25 ppm

[Zale2101]

Hey there Caudata, I've got a question:

For the last few weeks in my 20g Axolotl tank the Nitrites have persisted at about .25 ppm. I know this is not good, and I've done a number of things to try to remedy it, including switching around my setups to give them a big ol' canister filter with a nice spray bar, and a couple of water changes.

One of my Axolotls, a leucistic, appears to have forwardly curved gills, possibly indicating stress. The other one in the tank, a white albino, does not have this stress indicator.

Am I myself stressing over this? I figured if it were really bad, my albino would appear stressed as well. Maybe something else is stressing out the leucistic.

Before anyone asks, my substrate is a fine sand. I gravel vac it periodically for waste and my tank has a couple of those marimo moss balls to pick up on the excess nitrates. Ammonia readings are persistently zero. Nitrates fluctuate, but are relatively low.

 

[Zale2101]

One more little detail:

The force coming off the spray bar is not really substantial. It doesn't seem like that would irritate them too much, despite the fact that the filter is rated up to 70 gallon tanks.

 

[Zale2101]

Still looking for help on this matter. I've done another water change to siphon out some of the waste in the sand, but no go. Nitrites still clinging to that low background level.

The tank is pretty well cycled and using a well established filter from another tank with a really good biological filter colony.

I can't imagine why they won't go away.

 

[dragonlady]

It doesn't sound like your tank is cycled if you are still getting a nitrite reading. When you say it is "pretty well cycled," doesn't sound like you are sure.

Check your source - the place where you are getting your water from for your water changes - just to rule that out.

Also, what type of test kit are you using? Strip type tests can give you false readings. If using a drop style test, check the expiration.

Now a few questions - Are you using any type of water treatment, ie dechlorinator? Also, what is your temp? How old/big is your leucistic? (I have noticed that as juveniles, my leucistics seemingly had a habit of holding their gills forward when something caught their interest) Is his/her tail tip curled too? How much water are you changing and how often? diet? substrate? - just trying to determine if there are any factors that could be stressing your guy and/or affecting the nitrite reading...

 

[Zale2101]

The tank is as I say, "pretty well cycled". I have had it maybe 6 weeks or so, but I've had the bacteria colony going far, far longer.

We've been using tap water filtered from a commercial Pur water filter, then treated with a dechlorinator. I always give a sufficient amount of time for the dechlorinator to do it's thing.

My test kit is a drop test kit I got recently, the expiration date is November of next year.

Temperature is between 66-68 degrees Fahrenheit (18.8 to 20 degrees Celsius). Both axolotls are about 3" long at the moment, maybe a little bigger. Neither has a particularly curved tail, except when turning tightly on the ground. I change about 25% of the water weekly. They eat mostly frozen bloodworms, thawed in warm aquarium water. And as I before mentioned, they're on a sand substrate.

Thanks for getting back to me, was beginning to think no one would see.

 

[dragonlady]

Thanks for answering all my questions!

It sounds like the tank is still cycling. If you are switching out filters/media and other things then you could in fact be stalling your cycle. Don't change anything else out and watch the cycle. You will need to keep your tank closely monitored for if/when the spike happens. If the nitrites spike, you will have to do a water change for the safety of your axolotls. Sorry, but if you've cycled tanks before, you know there is no set timeframe for cycling to complete.

The one with the curled gills - is it still eating okay? acting normal? does it hang out near the outflow of the filter? If it does hang out there, the outflow could be causing the gills to be blown forward a bit. If truly stressed, the diet and habits will change. When I say bent tail I mean that there will be a bent kink at the tip of the tail. Beyond that, as I previously stated - a couple of my leucistics often preferred holding their gills like that when small like yours - don't know why, they grew out of the habit.

Hope this helps.

 

[Jennewt]

Regarding the nitrite test kit, I would recommend testing some water that you know for sure does not contain nitrite, such as bottled drinking water or water from a healthy pond or rainwater. This will tell you for sure if the test kit is giving a false positive result.

 

[Zale2101]

Sorry it took me so long to reply. I've been busy with a new job at PetSmart.

I'm getting the general indication that there's nothing wrong from her. This little leucistic used to have a habit of floating at the top of the tank for a long period of time. She's not even doing that any more. They're still eating well and playing together. Water temps and conditions are better than ever, with the exception of those lingering nitrites.

Thanks for all the help.