Ask Questions About Cycling

[Essjay]

Make sure there are plenty of plants and that they are growing well before getting fish, then get them a few at a time. As it's the first time you've done this, take it slowly and keep checking ammonia and nitrite every time you add fish. The last thing you want is to rush things and suddenly find yourself in the middle of a fish-in cycle.

 

[aqua.land]

Make sure there are plenty of plants and that they are growing well before getting fish, then get them a few at a time. As it's the first time you've done this, take it slowly and keep checking ammonia and nitrite every time you add fish. The last thing you want is to rush things and suddenly find yourself in the middle of a fish-in cycle.

Thank you.
At the moment I only have one plant - a mini coco cave...
I'm going to the shop today to get some Java Moss, Dwarf Baby Tears, Amazon Sword Java fern and maybe Anubias.
However that may be a bit too many plants, but that is what I am choosing from

 

[Essjay]

See if you can get a floating plant as well - Salvinia, water lettuce, amazon frogbit, water sprite, or even hornwort or elodea (aka egeria) used as a flowing plant. Plants need nitrogen (in ammonia), light and carbon dioxide to grow fast. Because floating plants are on the surface they are close to the tank lights and they can get CO2 from the air, so they can use a lot of ammonia compared to plants lower in the tank.
A lot of the fish available to us come from rivers with overhanging vegetation so they like floating plants in the tank, another reason to get some

 

[GingerGandalf]

Ammonia is 0, nitrites have dropped to 0 and my nitrates are just about 0 as well! Am I cycled? I don't want to jump the gun and buy fish haha. Help!

 

[aqua.land]

Hi.
I would wait a little and see if they stay this way.
I had these levels and then I got some fish, and after a few days my nitrites became really high, so its better to be safe than sorry.
Have you had your "bacterial bloom" yet? It normally happens in tanks. It's when all the good bacteria begins to multiply and try and settle in the new tank, and the water will become quite cloudy. This will not harm the fish but I'm just interested to see where you are at.

Also, when buying your fish, make sure to introduce them slowly (not all the fish at once), and make sure the other parameters eg. pH, KH, GH match you fishes needs.

 

[FishGuest5123]

You may not get a bacterial bloom, I never have. However, I would expect your nitrates to be high. Have you done a water change to lower them or is your tank heavily planted?

 

[Brian02]

Hi, I decided to totally change a tank I had (no fish left in it). I took everything out, cleaned, put in new sand, new live plants and dechlorinator. The filter and filter media are same as what was in the tank before. I’ve been adding food to try and cycle and increase ammonia for 3 or 4 days but still zero. If I’m using old filter media does it mean the bacteria was already there so I’m done? Or keep going.

 

[Essjay]

There are three possibilities, maybe even all three together.

1. Food
The food will need to start decomposing before it breaks down to ammonia so you may not have waited long enough yet.

2. Bacteria
Did the filter media become totally dry or did it stay even just damp while you redid the tank? We now know that filter bacteria can live in media that's damp, it doesn't need to be in water all the time. And the bacteria don't die in 24 hours without food as used to be thought, they go dormant then die months later.
It could well be that you have a lot, if not all, the bacteria still alive in the filter. You will have lost the bacteria that were in the biofilm on the tank walls, and in the old substrate and on the old plants but there are probably some left in the filter.

3. Plants
You also mention plants - are they live plants? Plants use ammonia as fertiliser, so they would take up any ammonia made by the decomposing food.
If you do have live plants, and a good number of them and they are actively growing, they will take up ammonia faster than the 'filter' bacteria. In this scenario, wait till you are sure the plants are growing well, then add the first batch of fish.

 

[Brian02]

There are three possibilities, maybe even all three together.

1. Food
The food will need to start decomposing before it breaks down to ammonia so you may not have waited long enough yet.

2. Bacteria
Did the filter media become totally dry or did it stay even just damp while you redid the tank? We now know that filter bacteria can live in media that's damp, it doesn't need to be in water all the time. And the bacteria don't die in 24 hours without food as used to be thought, they go dormant then die months later.
It could well be that you have a lot, if not all, the bacteria still alive in the filter. You will have lost the bacteria that were in the biofilm on the tank walls, and in the old substrate and on the old plants but there are probably some left in the filter.

3. Plants
You also mention plants - are they live plants? Plants use ammonia as fertiliser, so they would take up any ammonia made by the decomposing food.
If you do have live plants, and a good number of them and they are actively growing, they will take up ammonia faster than the 'filter' bacteria. In this scenario, wait till you are sure the plants are growing well, then add the first batch of fish.

Thanks. The plants are live - I have 3 of them in a 20gallon tank. The filter media was not kept in water as I totally drained the tank but it was only empty for maybe less than a week so the bacteria may still have left. I’ll keep adding food and make sure doesn’t spike and that I’ve given it enough time to breakdown?

 

[Essjay]

Three plants in 20 gallons isn't really enough for 'silent' cycle - in other words, 3 plants are unlikely to take up all the ammonia made by a tankful of fish.
Even if the filter media was barely damp, most of the bacteria would survive. It's being totally and utterly dry which kills them.

I tend to work on the 'better safe than sorry' principle so I would rather see you add more fish food that risk getting fish too soon

 

[PearlTigress]

Hello! I'm receiving a fully set up and functioning 75g tank with a canister filter and a few large fish. In a month or two I want to set up a 29g for my son. Can I have a more or less instant cycle by seeding the HOB filter media in my 75g (for how long?) and maybe some substrate as well? Fill up the 29g on his birthday, put in the seeded filter/substrate, put in a few fish?

 

[Essjay]

I would see if I could squeeze the HOB's media in your canister, preferably sandwiched in the middle the canister's media.

 

[PearlTigress]

I would see if I could squeeze the HOB's media in your canister, preferably sandwiched in the middle the canister's media.

Sure! I imagine I can, or I'll sure try.

 

[FishGuest5123]

I seed all of my tanks. I put used media in the filter and even lay some just on the substrate. If you have used substrate, you can also put some in an old stocking or panty hose and tie it off. Then place it on the substrate. The more you put in, the faster it will take off. If no fish yet, feed it a little fish food or ammonia too. I usually have a cycle within a few hours this way.

 

[Essjay]

Forgot to answer the 'how long' part of your question.

I would put the HOB's media in the canister as soon as possible. The longer it's in there, the better.