View Full Version : A ? about ammonia and nitrite toxicity
Cloud-9
06-05-2003, 10:45 AM
I don't have my fish disease books with me, so I need a little feedback in order to help a fellow hobbyists. Exposure to fairly high levels of ammonia or nitrite can cause a fish to stop eating. Now, will the fish start eating again as soon as the water gets better, or do you need to do something in addition to that?
I recall reading that metronidazole or methylene blue can be used to "reverse" nitrite exposure. Please confirm that, as I do not have access to my books right now, but I need to know quite soon. Also, which of the two is used to "reverse" ammonio exposure?
beviking
06-05-2003, 11:45 AM
I'm not familiar with that specific ailment/remedy combo. I will say that ammonia can cause gill damage if it gets too high. If the fish's gills are damage and it is having trouble breathing, it will be less likely to eat.
Nitrite oxidizes hemoglobin in blood, creating methemoglobin which cannot carry oxygen. Again, if the fish is having trouble getting oxygen, it is not likely going to eat.
I would do some water changes to eliminate any ammonia and nitrite while you're awaiting an answer. Hopefully someone who knows something will chime in on your exact question. Good luck!
Mantis_22
06-05-2003, 2:51 PM
Just remember this as a rule of thumb for future questions...
NH3 is toxic at high levels (Also affected by High PH)
NH4 is Safe and is created once the ammonia step is completed unless built up over time
May I ask how many fish are you cycling with? An ammonia spike that high usually means your overstocking buddy lol. I have 4 cichlids in a 10 gallon temporary and the ammonia never hit almost 1 PPM with water changes every week. So something is up.
wetmanNY
06-05-2003, 4:40 PM
Longterm exposure to toxins can cause irreversible gill damage. With less long exposure the inflamed gill lamellae will heal. Methemoglobinemia from nitrite is reduced as the fish produced fresh supplies of hemoglobin.
The emergency is in eliminating all detectable traces of ammonia and nitrite. "Undetectable" is the only okay level.
Cloud-9
06-05-2003, 5:09 PM
mantis-22: I am not cycling anything. I am trying to help another hobbyists on another message board (gasps, yes, I also visit other message boards! :) ). Anyway, I do not know the exact cause of his/her fishes not eating. But I believe it might be exposure to temporary slightly high levels of ammonia or nitrite. The conditions have been removed causing this problem, but the fish are still not feeding. I almost suggested methylene blue, but I was not sure if that is the one to use or metronidazole to "reverse" the poisoning.
wetmanNY: Yes, that is true. The problem is how to get the fish back to feeding. I would think that simply removing the toxic substances would get them back to normal. But apparently, may be not.
beviking
06-06-2003, 11:29 AM
Originally posted by wetmanNY
Methemoglobinemia from nitrite is reduced as the fish produced fresh supplies of hemoglobin.
...and increased if the nitrite isn't removed. I would do some water changes to eliminate any ammonia and nitrite...oh, I already said that!:p ;)
Cloud-9, hopefully the damage is minimal and will heal with time. Hopefully, b4 the fish starve:( .
" NH3 is toxic at high levels (Also affected by High PH)
NH4 is Safe and is created once the ammonia step is completed unless built up over time"
???
NH3/NH4+ are in equilibrium whenever either is present or generated in the tank water. The relative proportions of each are determined by the water's pH. There is nothing about "once the ammonia step is completed" involved.
KateA.
06-07-2003, 10:03 AM
Wow! :p Some really good thoughts here and I'll just reiterate a few of them. I'm not sure what "reverses" ammonia and nitrite exposure, if anything really does. But while these fish were exposed to them, no matter the amount and duration, they could have contracted a parasite or some other infection that just isn't obvious yet. Frequent, small water changes, a boost in tank temperature a couple degrees, the addition of salt or Melafix.......any of these could be helpful until it gets figured out further. These have been very useful to us in the store when we are afraid medications in general are too risky to a whole system of fish or when we don't see anything obvious. Good Luck to your fish friend!
Cloud-9
06-07-2003, 11:36 AM
Thanks for the responses. I found my books and the answer. I believe Methylene Blue would help "reverse" the effects of nitrite exposure.
wetmanNY
06-07-2003, 1:33 PM
The effect Cloud-9 was reading about may be at www.rxmed.com/ under "methylene blue" Methylene blue being used to counter nitrite poisoning in humans...
But I would think water changes are more essential. A little chloride in the water (from potassium chloride or even common salt) competes with nitrite and minimizes the uptake of nitrite that produces methemoglobinemia in the first place.
Is the stress resulting from methylene blue's toxicity taken into account? Has this treatment been applied to fish?
Sounds like radically aggressive treatment countering poor fishkeeping practices...