Fish into fish less cycle

[Lostatsea]

I had an aquarium many years ago but decided to get back into the hobby. In a non-traditional way we bought some minnows for fishing but came back home with more than we thought so I got the wild idea to start an aquarium to keep them weekend to weekend. I went out and bought a 20L with a HOB filter rated at 40gal and a bubbler. Everyday I would perform a 50% water change to try and keep ammonia down but we still lost several fish. After 1.5wks I had put a log decoration and it seems one of the large minnows had died inside the log and began to decay. I decided to pull the decoration and get rid of the rest of the fish because I couldn’t keep ammonia below 4ppm. It’s been 1wk since all the fish have been removed but I still test about 3ppm ammonia everyday. Will a traditional fish less cycle happen? There’s quite a bit of uneaten food and debris still in the gravel I added the 3rd day of setting up the tank. I just bought some Seachem stability and I’ve been dosing for 3 days.

 

[Retired Viking]

Hello and welcome to the forum. It takes time for the bacteria to form and grow to the right amount to take care of the ammonia somewhere between 4-6 weeks. Are you looking for this tank to be a fish stocking tank for minnows? Bacteria forms on surfaces so it is good to have things in the tank and it will also form in your filter and gravel.

 

[Lostatsea]

I think it’s turned into a community tank and from now on we will only buy enough minnows for 1 weekend of fishing. I guess my main concern is I keep seeing ammonia even after not having any fish in the system for over a week. Once it drops should I get ammonia drops to keep feeding the bacteria until the cycle is complete?

 

[JuiceBox52]

I think it’s turned into a community tank and from now on we will only buy enough minnows for 1 weekend of fishing. I guess my main concern is I keep seeing ammonia even after not having any fish in the system for over a week. Once it drops should I get ammonia drops to keep feeding the bacteria until the cycle is complete?

Have you been doing large water changes to remove the ammonia?

 

[Lostatsea]

Have you been doing large water changes to remove the ammonia?

I did do 50% water changes daily until all the fish were removed. I haven’t changed any water since because the ammonia has been staying around 3-4ppm for the last week without fish.

 

[Essjay]

I would leave the tank with the ammonia as it will cycle. Tetra Safe Start should speed it up. Putting live plants, especially floating plants in the tank will also help as they take up ammonia as fertiliser and don't turn it into nitrite.

If you want to do a cycle without plants, you can follow this method https://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/ Follow this as though you have just added the first dose of ammonia.

 

[Retired Viking]

If you want to do a silent/planted cycle good floating plants are moneywort, hornwort, water sprite and anacharis. You can let them float or plant them in the gravel. Also good floating plants that just float are frog bite, salvinia and duckweed. All these plants absorb ammonia at a higher rate than plants like java ferns. If you let them float they absorb ammonia even faster because they can exchange gases (co2/oxygen) faster on the surface.

 

[Lostatsea]

So I purchased an active sponge filter from angels plus and put it in the tank Thursday. Ammonia was steady at 3ppm with 0 nitrite and 0 nitrate until today. It dropped to .25ppm ammonia and rocketed to 5+ppm on nitrites and 30ish nitrates. I added a little pure ammonia to bring it upto 4ppm and retested 1hr later and nitrites are still 5+ and 80ppm nitrates. Should I do a water change to bring down the nitrates?

 

[FishGuest5123]

So I purchased an active sponge filter from angels plus and put it in the tank Thursday. Ammonia was steady at 3ppm with 0 nitrite and 0 nitrate until today. It dropped to .25ppm ammonia and rocketed to 5+ppm on nitrites and 30ish nitrates. I added a little pure ammonia to bring it upto 4ppm and retested 1hr later and nitrites are still 5+ and 80ppm nitrates. Should I do a water change to bring down the nitrates?

. Did your ammonia drop any? You may want to do just a 25% change. Sounds like you’re close now. Don’t add anymore ammonia after water change. If you have 0 ammonia and nitrites tomorrow and still have nitrates, dose ammonia one more time. If it drops back to 0 ammonia, 0 nitrite, and you have nitrates after 24 hours, then you are cycled. At that point do a large enough water change to get nitrates down to 5-10ppm. You can then add fish slowly. Continue to watch your numbers and do a water change every time nitrates get over 20ppm. If you do a 50% water change it will cut your nitrates in half. Great job! .

 

[Lostatsea]

. Did your ammonia drop any? You may want to do just a 25% change. Sounds like you’re close now. Don’t add anymore ammonia after water change. If you have 0 ammonia and nitrites tomorrow and still have nitrates, dose ammonia one more time. If it drops back to 0 ammonia, 0 nitrite, and you have nitrates after 24 hours, then you are cycled. At that point do a large enough water change to get nitrates down to 5-10ppm. You can then add fish slowly. Continue to watch your numbers and do a water change every time nitrates get over 20ppm. If you do a 50% water change it will cut your nitrates in half. Great job! .

yes, the ammonia dropped to .25 then I added a little powered ammonia to get it back to 4ppm. Which .45grams is hard to measure even with a tiny scale. Tomorrow I’ll do a 50% water change and see what the tests say.

 

[Essjay]

Don't add ammonia until you've reached certain targets. If you add too much ammonia there will be so much nitrite it will stall the cycle. Each 1 ppm ammonia is turned into 2.7 ppm nitrite so it doesn't take much ammonia to make 15 ppm nitrite, the stall point.

If this was my tank, I'd do a water change to get the ammonia down to 3 ppm then start following this method https://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/

As you've added a second dose of ammonia, go from this part

If at any time after the first ammonia addition (Dose #1) you test and ammonia is under .75 ppm and nitrite is clearly over 2 ppm, it is time to add more ammonia (Dose #2). Add the same full amount as you did the first time. Now, begin to test the ammonia and nitrite levels every other day. (You should be seeing nitrate soon if you have the kit.)

 

[Lostatsea]

. Did your ammonia drop any? You may want to do just a 25% change. Sounds like you’re close now. Don’t add anymore ammonia after water change. If you have 0 ammonia and nitrites tomorrow and still have nitrates, dose ammonia one more time. If it drops back to 0 ammonia, 0 nitrite, and you have nitrates after 24 hours, then you are cycled. At that point do a large enough water change to get nitrates down to 5-10ppm. You can then add fish slowly. Continue to watch your numbers and do a water change every time nitrates get over 20ppm. If you do a 50% water change it will cut your nitrates in half. Great job! .

So I did a 50% water change and then tested the next morning and ammonia was very low around 1ppm with 0 nitrites and 0 nitrates. So I added a .45grams of ammonia to bring it up and it’s been at 3-4ppm of ammonia and 0 nitrites and 0 nitrates for the past couple days. I beginning to think I maybe forgot to treat 5 gallons of the water change? Everyone that says they used live filter bacteria was cycled in 3 days and mine was on track then I messed something up. since I was doing so many water changes when fish were in the tank I was really good about treating each bucket of water. Did I kill all the bacteria?

 

[Essjay]

I have never used bottled bacteria during a cycle, but I think it takes longer than 3 days. I know it can take 7 weeks without (that's how long mine took) but still up to a couple of weeks with a bacterial starter.

If you forgot to use dechlorinator it will just delay things. I would add some more bacteria and follow the method I linked to in my last post. It should go a lot faster than when I cycled a tank.

 

[FishGuest5123]

Essjay is correct. It still takes more than 3 days with bottled bacteria. I think closer to 2 weeks.

 

[Lostatsea]

Essjay is correct. It still takes more than 3 days with bottled bacteria. I think closer to 2 weeks.

Technically the tank has been setup for 4wks now. I think it went through some kind of cycle when I put that used filter material in the tank but somehow all the bacteria just stopped after that water change.