Tetra Won't Eat

[Fish Kate]

I've had a school of 6 flame tetras in my son's 10gal since last fall, but lately they've begun refusing to eat and are dying off one by one. There are no other tank mates. I've tried two different flake brands, shrimp pellets, betta bites, algae wafers (basically every food I have in the house).

Is there some special treat I could tempt them with? Are they just short-lived and dying of natural causes? The water parameters have been good and stable for over a year; nothing has changed in the tank.

Thanks for any suggestions.

 

[CaitxSith]

You can look for any nitrite, ammonia, or nitrate (not too much). Or it could just be that they're full but something else is killing them... That happened to me also..

 

[plah831]

Well, even if they are short-lived, it's highly unlikely that they would be dying all at the same time. Even if they were born in the same clutch, the odds of that are remote. It makes much more sense to me that if they start feeling ill at the same time, it's because they're reacting to the same thing in their environment.

I agree with Cait that we need to look for external causes, starting with ammonia/nitrite/nitrate.

 

[Fish Kate]

Okay, I do weekly 2/3 water changes (the last one was two days ago) and my parameters today read: Amonia 0, nitrate 20ppm, nitrite .5ppm. I do have very hard, alkaline water. Any suggestions?

 

[plah831]

hardness and alkalinity aren't that big a problem to fish as long as they are stable. My GH is 14 degrees, KH 8 degrees, and pH 8.0 and all my fish are thriving.

Nitrites in your tank are high. The "safe" level is 0.25 ppm AT MOST, 0 ppm is ideal. So it seems your tank is possibly going through a mini-cycle. I'm guessing you changed filter media recently? I suggest keeping up with water changes until those go away. It may take 3-4 weeks, as I've found the nitrite stage to take longer and be more susceptible to changes.

 

[Fish Kate]

I actually threw out my charcoal filter a couple weeks ago because of reading on these forums that they stop working after a few days...I kept the regular particle-filtering media in place...could that be the problem? Should I put in a new charcoal filter? I will do extra water changes to bring down the nitrite level. Thank you!

 

[plah831]

yup, the carbon is a great place for your beneficial bacteria to settle on. You can just replace the pre-bought inserts with a filter sponge and some floss for mechanical filtration. That way, you still have a surface for the bacteria, with no carbon

and remember to rinse the sponge every once awhile with dechlorinated water. Tap water will kill the bacteria and send you into another mini-cycle. No need to throw away the floss or sponges until they fall apart.