Can A Fishless Cycle Stall?

[Boulder Fish]

I have a 20 gallon tank (with a couple of live plants), which I began a fishless cycle on about 3 weeks ago. I chose to follow the "Add and Wait" method detailed in rdd1952's pinned, "Fishless Cycling," article. This is how it has played out so far:

Week 1: Brought ammonia levels up to 5 ppm, which dropped to zero after 7 days.

Weeks 2/3: Brought ammonia level back up to 4 ppm, which dropped to zero after 2 days, and nitrates began to register/climb. (No nitrites). I added ammonia each time it dropped back to zero, which continued to be every other day, for 10 days.

mid Week 3: (10 days after my initial ammonia drop I added the requisite ammonia again, along with some iron for my plants) It has been 3 days since then, and the ammonia and nitrates seem to have stalled (still no nitrites present) I tested yesterday morning, last night, and again this afternoon. Using my API Master test kit, I get 1 ppm of ammonia and 5 ppm of nitrates each time. (I had some leftover Jungle brand test strips, which also register the 1 ppm of ammonia, but read the nitrates at a much higher level of 80 ppm, and again 0 nitrites)

Any ideas on what might be going on?
Is it possible the addition of iron has affected the bacteria or the test results?
Should I be seeing nitrites by now?

I chose the "Add and Wait" method because it sounded more expeditious. But, I am certainly willing to take all the time necessary to create a hospitable environment for my future fish friends, so I can switch to the "Add Daily" method if it will get my nitrites in gear...

Thank you, in advance, for any advice/opinions.

 

[rabbut]

Fishless cycles can stall, and do so fairly frequently for various reasons. What is your pH on? After three weeks, I'd say the nitrate reading given by the strips is actualy more accurate than the API kit surgests. Re-read the instructions, as their Nitrate kit is very hard to use accurately This is quite unusual, hence why I surgest that there may be an issue somewhere
Low pH caursed by increased levels of nitrate are the main caurse of cycles stalls, so please post your tanks current pH

All the best
Rabbut

 

[Boulder Fish]

You definitely guessed right about the pH. It is currently at 6.2

It has been fluctuating wildly (day by day) throughout this cycling process (as I was prepared to expect by some of the articles I read), but now that you've asked, it occurs to me that it has stayed down at that level for the last three days.

 

[rdd1952]

I would suggest a large water change to get the pH back up and things should pick back up.

 

[Boulder Fish]

Thank you both.
I will do that, and let you know how it goes.

...Off to reinvigorate this cycle!

 

[Boulder Fish]

I did a 50% water change Saturday.
My tap-water pH is 7.8
The tank pH now reads 7.0

Would another (or bigger) water change raise it further?
Do multiple water changes have an adverse effect on the cycle itself?

Or is this the time I just have to sit back and see what happens?

 

[Jazee B]

hi i'm fishless cycling myself at the moment and Rabbut diagnosed my stalling cycle as a drop in pH. It has happened twice now and as Rabbut advised I added some baking soda just to keep things steady so I could get through my cycle. I have now almost at the finish line. These people on here are fantastic, I've asked so many questions and they always reply and give handy hints and tips. Good luck with it all. Becky

 

[waterdrop]

Yes, "large water change" during fishless cycling often means 90% (all the water except that in the external filter if you have one) or somewhat less depending on convenience. Sometimes if you are in a rush it is easier not to turn off your filter so you don't remove water below the intake pipe, or sometimes you have plants and don't want the level to go too low and disturb their planting in the substrate. Doing another such change later can further up your pH in the direction of your tap reading without resorting to baking soda. Don't forget to re-charge your ammonia after each water change and of course the replacement water should be conditioned.

~~waterdrop~~

 

[Boulder Fish]

It is now two weeks later in my fishless cycle, and I am still having problems with pH.
I did the 90% water change on June 2, and that helped get things going again, though the pH measured 6.8.
However, this week (8 days later), the pH dropped again to 6.2.

I did another 90% water change, brought the pH back up to 7.6 on Tuesday, and recharged the ammonia.
Now Friday, the pH has dropped again to 6.2.
Ammonia - 0.25 ppm
Nitrates - 80 ppm (my highest yet)
Nitrites - 0 ppm

Is it time to add baking soda? (quantity?)
What happens if I add coral?

Thank you all.

 

[Amunet]

It's suggested that baking soda be used as the last possible method to raising pH.
I used it though and still do for my tanks. You'll have to test out how much you use. Try adding in a teaspoon as first. Wait an hour after adding it and test pH to see where it put it at. Add more if needed.

I haven't had luck w/ coral so I can't comment on it. I just know it slowly raises the pH and keeps it steady.

With baking soda, you're going to have to add more in every water change.

Do a test w/ your tap water. Take some and put it into a cup and leave it out for a few day and test the pH to see if it changes any. Just to see if it's b/c of the cycling process that's causing the pH to get so low, or if it goes down low on its own.

 

[waterdrop]

Yes Boulder, good info from Amunet.

Coral is slow but steady and is the method of choice when raising pH with fish.

During fishless cycling you have that option but you also can use the more quick (both faster to raise pH and quicker to need to be replenished!) baking soda. As the fishless cycling tank is really just a soup for growing bacteria, you can really do whatever it takes to optimize it for the bacteria. Later you will change it all out for fresh water before fish, and baking soda will not hang around in the filter or be a problem for those fish, so its an ok thing to use.

For a 20G tank I would go ahead and do a large water change, add two teaspoons of baking soda (make sure its not baking powder, must be pure sodium bicarbonate - baking soda) and recharge your ammonia to 5ppm (or whatever level you currently want) and then run all your tests after waiting a while. Over time I've decided these bacteria, especially the N-bacs, really like a pH of 8.0 or so (precision is definately not important here) and I would just keep careful log notes and play with the water changes and baking soda to be keeping things in that target range (with the API pH kits you will have crossed over to the High pH and between the two kits its hard to really know, but you just want to be very roughly there near 8 (near 8 is so, so, much better than being down around 6.)

~~waterdrop~~

 

[SOLEXIS]

Hi
I have finished with my NH4 and NO2 pics. Just by adding bacteria using a biological media in my filter, of course.
Against NO3, a good preventive as JBL Bionitratex would help a lot to reduce this value during a year.
Stop the water change, just wait and add bacteria (Denitrol, I am still a JBL german addict !)

 

[rabbut]

Though you can use nitrate removing products, I usualy guide people away from them Some are dangerous, but not all. Seachem Purigen has recently come to my attention as being a good one, though I have not used it myself... I stear away from such products, as nitrate readings can give us a guide as to how many other toxins that we can't test for are in our water, thus giving us que to waterchange

Water changes are the most important thing for running a system long-tearm and DO NOT damage a cycle, despite what many believe If you whish to waterchange, waterchange as a post by Bignose in the scientific section indicated that they may actualy speed up a cycle.

A mature system will need about 15-20% weekly waterchanges, or 25-30% forghtnightly minimum. You could do 50% monthly also, but the shock to the fish of a sudden drop in toxins may be a bit too much. The general consensus is little and often is best. My own systems get 30-50% weekly

HTH
Rabbut

 

[SOLEXIS]

Though you can use nitrate removing products, I usualy guide people away from them Some are dangerous, but not all. Seachem Purigen has recently come to my attention as being a good one, though I have not used it myself... I stear away from such products, as nitrate readings can give us a guide as to how many other toxins that we can't test for are in our water, thus giving us que to waterchange

Water changes are the most important thing for running a system long-tearm and DO NOT damage a cycle, despite what many believe If you whish to waterchange, waterchange as a post by Bignose in the scientific section indicated that they may actualy speed up a cycle.

A mature system will need about 15-20% weekly waterchanges, or 25-30% forghtnightly minimum. You could do 50% monthly also, but the shock to the fish of a sudden drop in toxins may be a bit too much. The general consensus is little and often is best. My own systems get 30-50% weekly

HTH
Rabbut

Me again!
I agree with what you say Rabbut. But how many people is going to do a weekly water change? If it was the case, no products will be necessary, except the mineral because you had to use RO water to avoid all the bad element from tap water (PO4, chimicals...)
So again, I understand your meaning but I prefer use some bacteria regularly and make a monthly water change with RO even if it is not the same.

How have you learnt so many things about fishkeeping? Just because you are a fishkeeper for a long time? I am impressed

 

[waterdrop]

Hopefully all the beginners who have come through a period with TFF have become aware of the need for water changes. Water changes, in my opinion, are one of the great secrets of good aquarists, and precisely because "no products will be necessary!" There certainly are cases where very experienced aquarists with very stable long running tanks will disuss or experiment with fewer water changes, but for most of us beginners, water changes are one of the most rewarding skills to learn.

Tap water usually turns out to be exactly the baseline starting point that a good tank needs. Sometimes people with extremely soft water will have to resort to crushed coral to raise their KH and pH. On rare occasions people will have to resort to RO water, either to bring down the KH/pH of very hard water or because of other problems, but I think TFF members would estimate that these are a fairly small percentage of cases (members agree?)

~~waterdrop~~