Is there a great threat to using live bacteria?

Question

I need some help, fast! I did a recent nitrate/nitrite test after a lot of work on my fish tank, and my tests have been running up a high level of nitrite. (Somewhere between 0.5 - 1.5 ppm) Which is really stressing me out!! I just did a partial water change (~30%) yesterday, but today, I still have that same value for the nitrite! How should I lower it?? I've just done a 90% water change about a week ago too, so I really don't know how much a water change might help...

I did purchase live bacteria (bottled) a short time ago, because our bio-filter is a month or so new, and I think my nitrite levels are because of the new filter. So I've bought the bacteria, and I've added doses twice now, the last dose just on Sunday.

I'm wondering, with these high levels of nitrite, should I add some more bacteria? Is there any risk to possibly adding TOO much bacteria?? What are other possible solutions??
Please respond soon! Thanks!

Answer 1

In your case, there wouldn'y be any worry about there being too much bacteria. The bacteria involved in the nitrogen cycle are very specific. So there's no possibility of them causeing disease, or other things people associate with bacteria. If there are more than the ammonia and nitrite can support, some will die. The same thing happens when a tank cycles without adding the bacteria. They reproduce rapidly in the tank (creating the traditional "cloudy water" or "new tank sysndrome"), but once the population reaches the point of being able to process any of these compounds, excess bacteria produced simply don't have the nutrients to survive and part of the population crashes. The numbers actually go up and down for a while until a relatively stable number is reached.

The only question would be is if the additive contains the correct (living) bacteria to do the job. You'll see a good range of opinion on the effectiveness of these additives. See this link for more info on the bacterial additives - most of the applicable info is in the first few paragraphs: http://www.skepticalaquarist.com/docs/nutrient/nitcyc.shtml

Also, if you use Amquel to reduce the nitrogen compounds in the tank, this (according to the manufacturer) "removes/detoxifies all forms of chloramines/ammonia/ammonium/nitrites/nitrates from the water" and "does not interfere with the beneficial nitrifying bacteria or their food sources". But, the water will still test positive for these compounds. Which would lead me to ask if you have any fish in the tank and if they are reacting by gasping at the surface of the tank (typical reaction to high nitrites). I'd also discontinue the Amquel until the nitrite level decreases.

If there are fish in the tank, I'd do water changes of around 25% whenever the nitrite gets around 0.5 - this may mean several days of water changes in a row to reduce the level if it's at 1.5. If there are no fish, let the level go and wait for your bacterial population to build.

Answer 2

You mentioned the filter is about a month old. Is the tank the same age also? Do you have any livestock in there?

Bacteria will be found mostly in your substrate. They will only form and colonize when there is a food source available. The first kind that forms uses ammonia as food and converts it into nitrite. Then nitrite eating bacteria form and convert it into nitrate which is non-toxic. It will cause stress in your livestock which leads to disease and injury, but nitrate itself will not kill anything.

I used a product called Cycle when I first started. It is dormant bacteria that will activate when a food source is available. I've never heard of using too much beneficial bacteria. The more the merrier! I used a ton of Cycle when I started, but I didn't know any better! This was about 2 years ago and boy I wish I did more research back then.

As for the water changes: don't do more than 20%. Sometimes up to 50% (but Never more than that) is necessary if one of your inhabitants released a toxin, such as an octopus releasing toxic ink. Like the first guy said, too high of water changes will disturb your bacteria, and this may be the reason your nitrate is high now... it's been building up the past week.

Answer 3

Should be no problem. I believe Hagen Cycle says it is not possible to overdose this. The other brands are basically the same, bacteria spores waiting a food source to become active. It will speed up cycle time by about 30%. If nitrite is high, I'd do a 20% water change before adding more bacteria. After a water change, you'd need to anyways.

NEVER do a 90% water change! 20-25%. Otherwise you disturb the bacteria colony. Never do more than 25% two days in a row. If you need to do a 3rd, skip at least one day after the second.

Answer 4

There is no threat to you or to your fish from live bacteria that has been produced specifically for an aquarium. Be sure that you are keeping it refrigerated though, or it will starve off in the pouch/bottle and it won't be "live" bacteria (or particularly useful) anymore. :P

The best way to lower your nitrites is with frequent, small water changes. I would 25% every other day until your levels zero out.