Nitrites

Question
I have a 55 gal. freshwater, recently pulled carbon filters while treating my fish for ick per the instructions on the medication. I tested my water because its cloudy, the fish appear to have a white coating. All my levels are good except for Nitrites. I have 3 parrot fish, rainbow shark, tiger barbs, grommies, black tipped shark, tetras, and one goldfish. My husband has had large tanks before in the past and never experienced this problem. We have put the filters back in and he added a water conditioner. Will this correct the problem?

Answer
Hi Cynthia,

If your tank is testing positive for nitrites, it's worrisome - both ammonia and nitrites are toxic to fish, ammonia being more so. Water conditioner won't help...you need to get your tank balanced again.

Your medication might be what is causing the tank to become "uncycled" but I would also suspect your heavy fish load is contributing to the situation. You don't mention how many you have of each fish, but if you have several of each (except for the rainbow shark I hope, these fish need to be kept singly or will constantly bully each other) then you really need more room than a 55 gallon tank. Three full grown blood parrots and some tetras could "fill up" your 55 gallon easily - these fish get really big, and are quite messy. Nitrites and ammonia register when a tank is new (Google "new tank syndrome" for an explanation) but they also can occur whenever you have a tank that is:
a) overfed
b) underfiltered
c) overstocked
Or any combination of A, B, and C.

If you put the carbon filters back in the tank, the carbon probably absorbed all your medication and isn't going to work right. It's probably just as well, because if the fish are showing excess slime coat, they probably shouldn't be treated with a harsh medicine. They are already irritated enough from the nitrites being present.

Read this article to find out how to treat with salt and heat:
http://www.cichlid-forum.com/articles/ich.php

Basically, raise the temperature to 85 degrees - slowly, like maybe a degree every half hour - until you're at 85 degrees. You really need to add extra aeration, either from a bubble wand or powerhead - and drop the level of the water by an inch or so, so the filter can make more splash. Over the course of a day, add enough salt so that you have about 2 tablespoons per 5 gallons - this is about 25 tablespoons of salt since your tank probably has 50 gallons of actual water. You don't have to use "aquarium salt" - you can use kosher salt, or sea salt - but you shouldn't use table salt. Sea salt or kosher salt is exactly the same thing as aquarium salt, it just may not be ground up as finely. Do NOT use table salt or Epsom salt, none of these are the right kind of salt. You need non-iodized sodium chloride. After about 10 days, you can do a water change to dilute the salt and you can start slowly bringing the temperature back down again.

Before you begin treating for ich with salt and heat, you ought to do a big water change and lightly vacuum the gravel. Try to change at least 15 gallons of water, preferably 20-25 gallons. If you have a Python (Google python aquarium if you are not familiar with this tool) then this should not be too much work. Add the water conditioner (by which I hope you mean a dechlorinator that removes both chlorine, and chloramine, if you are using city water with sanitizer in it) as you are pouring in the new water. Make sure it's about the same temp.

Changing the water will dilute the nitrites. Keep an eye on them, as they are likely to climb again - but you need to get them as low as possible, ideally 0 ppm, before you start the treatment. Feed little, maybe one pinch of flake the size of your thumbnail, only once daily. Feeding less helps to prevent ammonia spikes. Fish can go for days (over a week, if well fed) without eating anything, so don't worry about them starving to death - that won't happen.

Here are some general aquarium sites to enhance your knowledge:
http://freshaquarium.about.com
http://badmanstropicalfish.com
http://www.wetwebmedia.com

I hope that helps, take care.
Nicole