Toxicity

[spider crab]

This may be a dumb question, but Is there any gradation of how bad ammonia, Nitrite and Nitrate are for your fish. I know they are supposed to be Zero (although I think I remember reading that Nitrate in low concentration may be acceptable), but I guess I'm wondering how serious a small concentration is versus a large concentration.
For instance if the Ammonia is .25 mg/L is that likely to deadly to fish in hours, days or a week?
What about a concentration of 1 mg/L of ammonia?
I know that it will depend on the fish species as to how sensitive they are.
If I come home for lunch and find my Nitrite is up to 0.3 mg/L should I immediately do a water change or would I be ok to waiting until I get home from work? How about at 0.8 Mg/L N02?

 

[bluemarlin]

In a well established tank you shouldn't ever see ammonia or nitrites above 0. If you do, something is wrong. Perhaps a dead fish or something is rotting in your tank. Even small amounts of ammonia and nitrites can cause fish health problems. Usually because this stresses them out and invites desease into your tank. The whole thing can snowball in a hurry. Is your tank cycling or how long has it been up and running?

 

[spider crab]

My tank's been up for about 3 months. From what people said on a previous post it seems likely I have just over stocked for my size tank.
Is it normal to see a small spike when introducing a new fish or is that just a sign that the tank is overstocked?
My question about toxicity is more of a general one. I'm mainly wondering how to react if i do experience a small or large increase in NH4, N02 or N03.
Presently NH4 and N02 are at zero, NO3 is at about 5ppm. Spec gravity 1.022 and Ph is at 8.3.

 

[heavenly damsel]

What part of NC are you from? I am in Jacksonville.

 

[ed r]

I don't think that question has a clear answer. Any amount of ammonia or nitrite is cause for concern. How long it takes to cause death depends on so many things. What types of creatures are exposed to it? Are they diseased? Are they stressed? Are they overcrowded? Healthy fish of many types may survive short term exposure to some levels. However, healthy fish exposed in this manner are much more likely to develop diseases such as ich because their defenses are weakened. Fish that are stressed or diseased to start with probably don't survive "mini-cycles". If your tank is in good shape and not crowded, adding fish gradually that do not move it to a crowded state should not cause ammonia or nitrite spikes. When they occur, something is wrong. Careful water changes can dilute the concentration and reduce toxicity. You cannot allow measurable ammonia or nitrite levels to continue to exist and expect most of your livestock to survive.

 

[fshhub]

nitrate, in a fish only, does not matter much(can be over 100 for most fish), in a reef, LOW, but depends on teh inverts as to how low
ammonia and nitrIte, should be 0 or unreadable, PERIIOD, any level is toxic to fish and inverts, no exceptions

 

[spider crab]

Thanks for the info folks! I thought there might to be too much variability to get a specific answer, but I thought I'd try. I found your comments helpful none the less. Especially about the fact that mini-spikes shouldn't occur unless something is wrong. Likely in my case I was oversotcked.
I'm in Raleigh NC, in answer to that question.

 

[demosthenes]

Who was it that said you were overstocked, because IMO you are not. Two are gobies, nice cleaners basically, and a clown. That seems fine to me. IMO there's something else that is wrong. What is your filtration?

 

[fshhub]

when you add fish, you could also experience a mini cycle or a small spike of some sort, this is the one reason we add slowly, to allowthe tank to rebalance itself berfore continuing

 

[spider crab]

In terms of the filtration question, I'm using a biowheel/carbon filter combination, along with all the live rock.
Now that you've brought up filtration, how often should change the carbon cartridge and or bio wheel. I have never been clear on that, although I have tried to wash off some of the gunk off the carbon cartridge using filtered water.

 

[fshhub]

never worry about changing the biowheels, if tha tis your chosen filtration
and carbon, i only use as needed, not all the time, if ever, but you could use it for a couple of weeks(maybe 3 or so) before changing it

 

[spider crab]

I've had my carbon filter in a several months at this point. Am I likey to cause myself problems by leaving it in or is just no longer effective. I was thinking it was good to keep it in as it would act as collecting point for the bacteria.
You mentioned that you use carbon only when you need it. Under what circumstances do you need it?