Cycling a new Tank

[Ronnie]

Hi there! 

I’m a major newbie and I’m trying to properly cycle a tank for the first time. I used already established media with the single fish I have now. He’s currently in a small hospital tank since he recently recovered from fin rot (I got him from a local grocery store and he had a lot of problems. He finally seems to be doing well now though!!) —I’m so ready to move him into his own big tank! 
 

I started cycling by putting in 2 ppm of ammonia, and dosed stability as the bottle instructs about 3 weeks ago. A week ago I added some tank water that I swished my established filter in to try to kickstart everything. It seemed to help!  The ammonia is now down to 0ppm, nitrite is somewhere between 2-5 ppm (I lean closer to 2) and nitrates are around 160 ppm. My real question is should I re-dose ammonia? I see so much conflicting info on the internet and I’m not sure what to do next. 🙃

Thank you!!

Edited June 8 by Ronnie

[xXInkedPhoenixX]

Hi @Ronnie! I'll preface this by saying I've never dosed ammonia, only used things like Stability and bottled bacteria to start my tanks. And I've done fish in cycling- which I probably wouldn't do with this little fish you have since he's clearly been through enough!  I'm wondering if you added some fish food to the tank? All you need is for that nitrite to go away (though nitrate is definitely high so that's gotta go down- easily done with a water change though, when you are ready). Does this tank have plants? 

Generally you don't need to dose ammonia with cycled material, just use it and you're ready to go within a week. 

In the cycled material case, I just keep a close eye on parameters when I add the fish and test every day. Dosing Prime whenever I see a spike after small water changes. 

[AllFishNoBrakes]

I wouldn’t re-dose ammonia. Bacteria’s are present and working. Just be patient and when that nitrite hits 0 do a water change and you’re off to the races. 

[Ronnie]

@xXInkedPhoenixX@AllFishNoBrakes

Thank you both so much for responding!

I have 4 small plants in the tank, and hope to add more with some time. They look good and healthy so far!

I was really hoping this is the advice I would get! I have a tendency to fuss over things wayyy too much. I’m glad to hear this is a situation where I don’t need to. 
 

My plan now is to wait for nitrites to drop to zero then do a 50% water change. At that point as long as nitrates are roughly 20 ppm am I set to put him in his new tank? 

Thanks again!! 

[xXInkedPhoenixX]

Yep! You should be good soon. I run my tanks about 40ppm Nitrate and my fish do well!

[AllFishNoBrakes]

Agreed. Once nitrites hit 0, do your 50% water changes and you should be good. Continue to monitor and test and you’ll develop your routine. 
 

Feels like FOREVER when your tank is cycling, but in the long run it’s really just a blip on the timeline of the tank. 

[Ronnie]

Okay—new problem. 🙃 I will spare you the details, but my sweet little toddler emptied the tank about halfway this morning. After cleaning up the HUGE mess, I retested the water and obviously my nitrite level has gone down slightly (about 1 PPM) is there anything I should do about it at this point? Should I add or change anything? 
 

I was almost a little impressed that she grabbed the aquarium vacuum and got it to work so fast. I was taking a little water off the top because I added some new hard scape. I was only gone for about 30 seconds. Toddlers man. They’re crazy. 🤣

[xXInkedPhoenixX]

Oh gads!  NEVER leave the food where toddler can reach then! If she can get a siphon to work they can definitely "feed" the fish with the whole can! 

Did you put the fish in yet? Just checking that after you filled the tank it's still at 1ppm Nitrite (I'm assuming yes). If it were me- if the fish is in there definitely dose with something like Prime. If not, maybe add more cycled material if you can, maybe sprinkle some fish food for some ammonia to get that to go away. 

 

Edited June 16 by xXInkedPhoenixX

[Ronnie]

Thankfully we already keep the food up high! My goodness this little girl gives me a run for my money. 😂🙃 I NEVER would have imagined she could figure out the syphon—but I wrong. So so wrong. 
 

No, he’s not in there yet! I will add some cycled material and food ASAP. Thank you!!

[Pepere]

I think if it were myself, and the fish is recovered enough you would otherwise move it,  I would largely empty the tank and refill it.  This would get your nitrates down .  If you were 160 ppm nitrate before, a 50% water change would only get it to 80 ppm which is still very high.

 

You have an established filter that handles the bioload you fish puts out.  I would put that filter assuming you can and it is not fixed in place along with the new filter. It should do pretty well handling the same bioload in a bigger tank.  The bigger tank will also give a much bigger buffer against rises in levels one fish can put out.  
 

I would feed lightly, and test daily.  The new filter as well as all the surfaces in your tank will with time develop beneficial bacteria.  In addition to the seeding from the old filter, the fish poo will help seed bacteria needed in the tank…

[xXInkedPhoenixX]

@Pepere I think @Ronnie is avoiding moving the fish until the tank is cycled because the fish has already been through treatments/not done well and so avoiding stress. I agree fish in cycling doesn't have to be stressful if you're diligent but I understand why the fish hasn't been moved too- been through a lot already. 

[Pepere]

Yes, but if current filter is moved over with fish, this really isnt fish in cycling…. Presumably the filter is handling the fish’s bioload.  Putting it in a bigger tank wont increase the bioload.

If the fish has not recovered sufficiently to return it to a tank then continuing as others have mentioned would be advisable.

 

Edited June 16 by Pepere

[JettsPapa]

I agree with @Pepere about doing a large water change now and moving the fish into the larger tank along with the filter, or at least the filter media.  If I had seen this when it was first posted that would have been my recommendation in the first place instead of doing a fishless cycle while leaving the fish in the quarantine tank.

[Pepere]

Just to be clear, new tank obviously has some nitrifying bacteria given the metabolization of ammonia and presence of significant nitrates.  And there is an existing cycled filter and we are talking 1 fish.

my recommendation would be much different if someone was in the midst of cycling a new tank and didnt have a fish already and did not have a cycled filter.

[Ronnie]

@Pepere @JettsPapa @xXInkedPhoenixX Thank you all so much for your input here! I have a lot to consider I guess. I know he’s getting bored in his quarantine tank but he has been through the wringer health wise. Decisions decisions. If his health takes a dive after I move him I’ll never forgive myself—but I’m so ready to see him in his big tank and happy. No one ever tells you about this stuff when you start your first aquarium! 😂🙃

[Pepere]

@Ronnie  how big is the big tank, and what species is the fish?

[Galabar]

It's hard to say whether you should add more ammonia.  Ideally, you'll want enough biological filtration to handle the fish that you will be adding.  However, there are two things that make that difficult to judge.  First, nitrifying bacteria can live a long time (even in a bottle) without ammonia and, once the tank is cycled, the level of biological filtration can increase quickly when new sources of ammonia are added.

So, that might leave you wondering, do I want to add more ammonia to get more biological filtration, or will my fish be Ok with a mini-spike of ammonia (which might not even happen) when I first add them?  Answer: I don't know, and, without a lot of experimentation, no one else does either. 🙂

Edited June 18 by Galabar

[Pepere]

I have read it recommended to continue dosing 4ppm ammonia until a tank can metabolize that dose fully to nitrate in 24 hours.  
 

If done this way, you have the biofilter grown to where you can instantly add enough fish that produce as much ammonia for a given size tank that produce 4 ppm of ammonia per day.

 

a single fish in a 100 gallon tank is simply not going to produce any more ammonia than it will in a 10 gallon tank.   The biofilter has to manage the ammonia output of the fish, not the size of the tank.  

[Ronnie]

Well, when I tested this morning ammonia was 0, nitrite was 0, and nitrates were somewhere between 5-10. I did a good water change early this AM, (and actually had to do another late in the afternoon because the driftwood I added the other day made the water super cloudy. 🤦🏻‍♀️) I think everything is finally on track?! If at all possible, I would love to do another water change to get the water crystal clear before I switch him over. Can I do that now or should I give it a day or 2? 
 

Honestly, I planned to still add the filter from his tank now when I switch him over. I figured why not. 🤷🏻‍♀️ Just as a precaution. 
 

@Pepere The tank is 10 gallons, and this is for a goldfish. (I know that’s not nearly big enough! He will actually be in our pond at our new house once we move in a couple of months. Just bridging the gap.) I love your explanation on the filter needing to handle the fish output, not the tank. That makes a ton of sense. 
 

Thanks again to all of you! I feel like I am learning so much from these forums. I don’t know how people start in this hobby without it! 

[Pepere]

Definitely add the old filter, without question. And test daily for Ammonia and Nitrites for at least a couple weeks.

 

as to cloudiness, water changes might not help much.  It might just return until heterotrophic bacteria on substrate, surfaces and filter build enough to take care of it.

A few weeks ago I woke up to a quarantine tank so cloudy it looked like the glass was frosted.  Itested for ph, Ammonia and nitrite which were all fine. 
 

I transferred a double sponge suction cupped filter I keep in all of my display tanks to always have a cycled filter to throw into a quarantine tank.  12 hours later water was noticeably better and 24 it was resolved where Iwouldnt have noticed it being off with a casual glance.  36 hours it was crystal clear…

[Ronnie]

@Pepere That is good to know! In this case it was definitely dirt (one more water change really cleared it up!)—but I have heard of bacterial blooms like that happening. 
 

I transferred him about 24 hours ago. So far he seems to be tolerating the change well! How long would you leave his old filter in for? 

[Pepere]

Unless you need it back in another tank, I would leave it in for a month.

With the fish transferred, I would be feeding lighter than normal, and I would test for ammonia daily for at least a week. Probably every other day for second week.

If you opt to not test as often, at the very least observe water surface daily for presence of nore bubbles than normal. You typically will see more bubbles as Ammonia levels rise…

 

 

[Ronnie]

@Pepere Thanks again for the help! I have been running both filters simultaneously since you posted this, fed lightly, and tested very very often. The transition has gone well—and our fish seems to be thriving!! We are getting ready to go out of town, and I want to get down to 1 filter canister before we leave (for simplicity sake for the guy watching our pets.) Would it hurt the fish to put the old filter cartridge in the new filter canister behind the newer (but already cycled) filter cartridge? 
 

Thanks again!! 

[Pepere]

It could impede water flow.  You could try it and see how if affects the flow.

 

you could just keep the old cartridge in the water, 

[Ronnie]

Gave it a try and the filter is flowing well! Over 24 hours later and everything looks great. Thanks again!