nitrite tolerance?

[claude saunders]

I've been reading up on nitrite tolerance of fish. As with many things, the answers are complex and dependent on many things. Here's my situation:

Added 12 healthy 4-6inch Bluegill to my fully fishless-cycled 60 gal tank (40 gal heavily planted media growbed). Prior to adding fish, my system would process 2-4ppm of Ammonia straight through to Nitrate in 24 hours (in my case, a quarter teaspoon of powdered ammonia gave 2-4ppm).

Once the fish entered, ammonia spiked briefly to 2ppm, and has been consistently zero for days now. Nitrite jumped to 1ppm and seems stuck there. So it would seem that I am processing ammonia faster than nitrite, so I have a bit of "nitrite backup" perhaps. Note that I have not fed fish since they were added 5 days ago, so I'm a bit confused as to why nitrites are stuck at 1ppm.

My concern is the fish seem listless and are not eating at all (5 days now). My understanding is that days of nitrite exposure are bad - at any level. My water is clean, warm (72 degF), I clean up any uneaten food, bottom of tank is clean. Ph is good at about 7.0. Water is heavily aerated, so I believe DO levels are high. Growbed is super-healthy and heavily planted.

So, would a nitrite level of 1ppm keep fish from eating? Do I need to be concerned about the 1ppm nitrite - enough to start doing water changing?

Or maybe my fish are just tired of seeing me hovering over them :)

[Bill E]

Simple answer to this question.  Yes.   Even though you cycled your tank before you added fish, the biological filter that was established was not big enough to support the 12 fish that you added to the system.  Any ammonia reading of more than 0 is BAD and any reading of Nitrite other than 0 is BAD.

[Chip Gregory]

Bill E said:

Simple answer to this question.  Yes.   Even though you cycled your tank before you added fish, the biological filter that was established was not big enough to support the 12 fish that you added to the system.  Any ammonia reading of more than 0 is BAD and any reading of Nitrite other than 0 is BAD.

[Chip Gregory]

Sorry, I am just learning the system. I have 4 bluegills in a 40 gallon tank and they are somewhat territorial. Also I said this before but I have fat happy fish because they are eating shrimp, ham and turkey. I have amonia level on 1 ppm occasionally and I do water changes.

[claude saunders]

Just a quick update. My dozen bluegills are now happily settled in and eating aquamax pellets quite well, and considerably more active. And yes, they do seem quite territorial. It's fun to watch them poke others away from a favorite location in the tank. Water chem is normal. So, evidently, they tolerated about 6 days of 1ppm Nitrite (and some ammonia backup too) without apparent ill effect. Thanks for all the info and support.