Can a tank "Cycle" in 11 days?

**pinsonpa** · 03-20-2008, 09:54 PM

I'm sort of a beginnner. I had a tank in college for 5 years but that was 13 years ago. Quite a bit has changed so I feel like a newbie. Anyway, here's what I have:

10 Gal. tank (used)
Penguin 125 Bio Wheel Filter (used)
Gravel (used)
Tetra submersible heater (used)
FISH: 6 Cardinals
PLANTS: 1 Java Fern and 1 Anubias Nana

My newly set up 10 gal. freshwater tank has only had fish in it for 11 days, but my Ammonia and Nitrite levels are zero and Nitrates are at 10 ppm. Does this mean my tank has "cycled"? Doesn't this seem pretty fast?

Before you dive in...here are some quick variables:

The filter and tank are "used" and had gravel with about an inch of water in it. I cleaned out the tank and rinsed the gravel with warm tap water (I assume this killed off any bacteria). I didn't clean the Bio Wheel but the previous owner said it had been dry for more than a week (I assume this killed off any bacteria).

I did use two caps full of Nutrafin "Cycle" but have since read several reviews saying it was a useless product with false claims. I also used a dose of Sechem's Neutral Regulator to dechlorinate the tap water.

The live plants came from established tanks at a reputable aquarium shop but these tanks didn't have fish in them (not sure if there were benificial bacteria on them, but supose it's possible).

The tank was set up for 7 days prior to adding the fish and plants. Over the last 11 days I have been feeding the fish Tetramin Pro Crisps (about 1 crisp per fish, or less, every other day). On day 11 of having fish and plants (day 18 for the water) I have a tank with Ammonia and Nitrite levels at zero and Nitrates are at 10 ppm. I used a Aquarium Pharm. Master test kit for my water tests and had my local aqaurium shop test the water too. I have not done any water changes.

Now that you know what I know....Does this mean my tank has "cycled"? Doesn't this seem pretty fast?

**A340** · 03-20-2008, 10:03 PM

Theoretically, one could have a cycled tank within a day or two.

Even though it's a used tank, you're assumptions that most of the bacteria died off is probably correct.

So, more or less, you started a cycle from scratch. You added fish for the ammonia source (be prepared to be pointed and lectured at on that one ;) ) and used Nutrafin Cycle for the bacteria source.

Like any product, you'll hear people say good things about it and others say bad things about it, just like Chevy and Honda, it's a part of life. Personally, I don't really have any experience with it. I've been using Seachems Stability for the last couple of years and have had nothing but success with it. In fact, I even use it for all of my water changes, absolutely great product. But, that's just my opinion.

Now, I don't want to say if that your cycle is complete or not, because you still may get a spike, so I'd just keep doing what you're doing and test it every day to see if there really are any sufficient changes or not.

Even though an average cycle takes about a month, it is possible to have it done in less time. But just keep an eye on it just in case.

**Lady Hobbs** · 03-20-2008, 10:13 PM

Your used gravel would have been a huge plus but only if it had been used in the last few days. If it had been bagged up and the bacteria allowed to die off, then you would have gravel that was like new again.

But, if it was recently used and you used a bacteria booster, yes you could and probably do have a cycled tank. Was the filter media also used?

Nice job!

**Sasquatch** · 03-20-2008, 11:00 PM

I'd lean towards a tentative "yes" with regards to a completed cycle. I'd still check the ammonia and nitrites a few more days, just to be sure.

A couple of potential explanations ...
- The plants, they probably carried some bacteria, enough to kick start the reaction.

- Your gravel wasn't completely dead ... If the tank was setup for a while, even with the cleaning, there was probably enough oxygen in the water to maintain them and enough decomposing matter to supply some ammonia.

- Dormant bacteria ... I'm not certain if cycling bacteria can do this, but it's not impossible. If the gravel was wet, it's possible that they went into some kind of "hybernation" and when you added the fish, they woke up again.

**Wild Turkey** · 03-21-2008, 12:50 AM

I agree, sounds like u got lucky and the tank cycled fast. I also hear bad things about "cycle" but i hear it works in up to a week where as biospira will work overnight. So id say this the gravel and filter's bacteria is most likley dead, the cycle must have done it. I would check my lvls everyday for a few more weeks, If the tank has cycled you should see some fluctuating nitrate lvls, if it has not, you shouldnt see any nitrate at all. In the future make sure u take care of this stuff BEFORE you add fish, because if u didnt have any fish in the tank a simple idicator would be add ammonia, and if its gone the next day ur tank has enough friendly bacteria and thus, is cycled. If ur considering adding ammonia, browse posts on "surfactants" or you will be sorry i promise. Very good luck to you and ur tank

**LosC** · 03-21-2008, 02:08 AM

I used Seachem Stability and it cycled my tank in 9 days.

**jbeining75** · 03-21-2008, 02:11 AM

With two seeded filters and socks filled with gravel I cycled a 55 gallon in 8 days... Depending on how seeded it is you should be able to cycle it. Good luck keep us updated!!!!

**SkarloeysMom** · 03-21-2008, 02:38 AM

It sounds pretty cycled to me. I'm guessing you wouldn't want to plunk in a whole bunch of fish at once just in case. Well, its a 10g right? You can't really plunk in too many more that you already have. Test it every few days for a while and you're probably good. It sounds like you got some seed bacteria from somewhere and it was just enough to get it going. I can see a small tank cycling that fast with seed bacteria. I've cycled a 2.5 and a 5g in 4 days that way.

**cocoa_pleco** · 03-21-2008, 03:15 AM

i use special blend bacteria, and i dont have to cycle my tank. when i fired my 90g up i had no seeded equipment, a few capfuls of special blend and i had full stock in a day without any ammonia issues

**Hairback357** · 03-21-2008, 03:18 AM

I have used these cycle boosters before and this is what has happened. I noticed next day that I had zero AM after adding 5ppm the night before and I had 0 Nitrites and 10 or so Nitrates. I also thought wow look at that fast cycle but it wasn't the case. Like 14 days later the Nitrites spiked and then gradually went down. I was lucky that I still had not bought fish yet and didn't believe the readings I was getting. I think these bio boosters try and keep toxic AM down while the tank cycles. The bacteria leaves these Nitrates in the water as soon as the next day. I still believe my two tanks I tried these two different products with helped speed up the cycle but not drastically. I tried to cycle a tank recently for 18 days without any boosters and still never cycled. I got fed up with waiting and then just added a filter from another tank and was done with that. I am impatient when it comes to waiting for a tank to cycle but if I were you I would be skeptical that your tank has cycled. From you description I highly doubt it.