My Tank is Cycling Again!

[Sasha]

On January 9th, I started cycling my 46 gallon tank. I chose the "Fishless Cycle" because it seemed like a quicker way to cycle a tank and there were many successes about it. I bought pure ammonia and added 1 drop for every 5 gallons. The filter, heater and gravel was already in place.

A week later, The Ammonia rose up to 5. I waited for a Nitrite spike, but for the next two weeks it remained at a safe level. I increased the dosage to 1 drop for every gallon, but still nothing happened. I assumed that I missed the Nitrite spike, even though I tested the water every few days.

I tested the Nitrate and they were at 12.5. I did a 75% water change because that's what the directions for the "Fishless Cycle" said to do. Now, the Ammonia is starting to rise again to an unsafe level. I still don't have any fish, but it looks like that tank is cycling again. Any advice?

 

[wetwetwet]

Fully cycling can take upto 6 weeks - quicker with warmer temps

I've never used pure ammonia but maybe someone else who has can help

 

[thecichlidaddict]

I'd say ride it out. Something went wrong, no big deal. Continue to keep an eye on levels, and remember to keep adding ammonia even after the nitrites peak and then bottom out - at this point with a steady supply of ammonia in the same amounts that you have been using the numbers should still measure 0, and nitrates should continually climb. Don't use too much ammonia or your bio-filter won't be able to handle it, go with the recommended amount.
Don't add any ammonia on the day that you are adding the fish, and only do that 75% water change right before adding them, on the same day.

 

[Sasha]

How long does it take for the Nitrite to spike? I have an Aquaclear 300 that's running everyday and still after two weeks there was no Nitrite spike. I started adding 1 drop for every gallon now because I don't think it cycled fully that last time. Any advice?

 

[thecichlidaddict]

If you are still measuring Ammonia then I'd suggest doing a 100% water change and taking a different approach. The water change won't interfere with progress so far, it just clears all of the ammonia out of the water.

Now figure out how much ammonia you need to get your tank to a level of 5 ppm. Add this same amount every day until you measure nitrites, when you can reduce the amount of ammonia to half of what you were using. Keep adding this half dose of ammonia as long as nitrites measure positive and up until the very day that you add fish. The 75% water change is done right before adding the fish to get rid of the nitrates that have built up and any ammonia that might still be present from your last dosage.

There is no exact time for nitrite to show. It could be a week, or it could be 2 weeks. It shouldn't go much longer then that.

You can speed up the cycle quite a bit by adding established bacteria to the tank. You can do this by obtaining filter floss from the tank of a friend or the fish shop and adding it to your own filter. Remember to bag it in aquarium water as you would a fish. Bacteria thrives in warm water, so raising the temp to 85 or so will also help, just don't forget to cool it off again for the fish.

Hope this helps