Ntrite damage questions

[daveedka]

I had an oops in the guppy tank this week concerning food. I cleaned it up pretty promptly, but with the plants, not as thouroughly as I thought. the next day I noticed some lethargy, and what appeared to be dis-orientation in some of my fish. I quickly tested and did a water change, ammonia 0, nitrite were at 4-5 ppm and nitrates had jumped to well over 40. this tank usually has nitrates between 15-20 before my weekly maintenance. The tank was only alone for about 5 hours so this all happened pretty quickly. The water change and vaccum got the nitrate back down to about .25 ppm and dropped the climbing nitrates back to 20. All of the fish responded within aout 15 minutes and were back to normal except one who has not been active since. He doesn't have clamped fins, and he is breathing pretty normally but he just quit being active. he was always a very active fish before.
What are the long term effects of short term nitrIte exposure, and should I expect him to get back to normal or is it possible he suffered some type of irreversable damage. He happens to be the only one of the guppies I have paid for so I imagine he isn't as hardy as the homegrown freebies I get from my brother.

 

[vato]

The affects are permanent gill damage. This could be the reason that your fish is not as active as he used to be. I can't really say why he would be the only one who is not back to normal especially if they are all guppies. The gill damage, will lessen with time, but never go away. Your fish will be able to live a perfectly normal life if the damage is not too severe. I'd say give him a couple days he may still be feeling a little "under the weather". If his condition doesn't improve, then it may never, but that is all for time to tell.

 

[RTR]

No, not quite. Ammonia damage is gill epithelium damage (scarring from the chemical burns), but nitrite toxicity is from inhibitory competition for O2 transport by hemoglobin. The nitrite ion attaches as would the O2, but does not release, so the fish suffer anoxia - they are in effect suffocating. Nitrite toxicity can be temporarily blocked by the chloride ion, Cl-, and it does not take much - half a teaspoon per gallon of NaCl (salt) or KCl will do the job.

Ammonia burning and scarring is over long-term at least partly reversible as new gill epithelium will be will be developed eventually, but original efficieny may not ever be restored. Nitrite toxicity is fully reversible if the fish has not died or suffered nerve damage from oxygen lack.

 

[vato]

Well there goes all my creidiblity!! Sorry about that daveedka, RTR is correct, what I was talking about was ammonia damage. So please give me another chance. Once the nitrite attach to the blood, they stay attached to the blood cells. They bond up to 5 times stronger than an oxygen bond. This means that it will stay attached to the blood cells for 5-6 complete circulations of the blood from the gills throught the heart and back to the gills. that they are unable to take up oxygen. There is no real permanent damage (at least noticably) if caught soon enough, which it looks like you did. The permanent damage that can arise is decreases gill capacity, which requires more/harder breathing. If this is what your fish has then, it may not recover. The thing is, in a completely cycled tank, there should be sufficient amounts of bacteria in your tank to insantly convert the nitrites to less harmful nitrates. So if your tank was only left for 5 hours before you vaccumed the food out, is that enough time really for the entire tank to become so imbalaced that the biological filter couldn't do it's job? can fish food break down so quickly? I had a similar incident with a young downs-symdrom boy who was facinated with water, and I got it in excess of 7-8 hours and all my fish survived! I don't know the answer, so that is why I'm asking.

 

[daveedka]

Thanks to both of you, Vato don't worry it's easy to get mixed up ( I do quite frequently), and in this case I thought you were mixed up, but wasn't sure enough to know that so I waited and BTW thanks for your very informative second post. I thought that nitrite was a blood O2 issue, and recognized the lethargy and confusion in the fish as poor o2. the ammonia test showed 0 but I'm sure at some point the ammonia level was at least slightly elevated. one of the things I'm learning with regards to plants is that I never see ammonia, but for the first week with the heavy fish load the nitrites did rise a little bit. and obviously during the aouto feeder dissaster the other day they climbed very high.

As far as the fish is concerned, I think his problem may have been more do to the feeding dissaster than the ensuing nitrites. last night he got pretty weak, and I felt it necessary to euthanize him but he showed signs of some bleeding around his vent and up until about an hour before I gave up on him he still didn't seem to be breathing abnormally, just very weak. all of the other fish including some very small fry are going strong, and even my ghost shrimp don't seem to be having any trouble. I have only had this fish about a week so it well could have been beyond my control as it was.

As far as Nacl helping, the tank is under quarantine for ich right now. I've seen enough flashing out of the guppies to concern me and now have the big tank totally free of ich. I went ahead with a salt treatment on the guppy tank to ensure I would never add ich back to my cichlid tank. so during the nitrite rise, the tank was at 2 tsp per gallon of salt (blind luck I guess)
Thanks again both of you.
Dave