Fishless cycling questions

[Wings_fan]

I'm currently going through a fishless cycle on a 65 gallon aquarium. I have ammonia eating bacteria, whatever I put it at it goes to 0 in 24 hours. The nitrite eating bacteria seem to be present, but not in high amounts. I say this because I have nitrates that increase over time.

Right now, I have 0 ppm ammonia, around 4 ppm nitrites, and around 40 ppm nitrates. My question is how long can I not put in ammonia to let the nitrite bacteria try to catch up before they start dying off?

 

[verochloeedgar]

I have exactly the same problem and I at week 6 of cycling! Ammonia disappears very quickly, nitrites and nitrates are always high. I did 2 o 3 partial 60% water changes and I continue to add ammonia as I understood that was the way. I also added some fish food. I heard on some YouTube videos that 50% of the bacteria population dies after 24h without ammonia but I don't know if it is true. Hopefully someone with more experience can help us!

 

[dalto]

In theory the bacteria colonies die rapidly but also expand rapidly.

When fishless cycling I usually do a big water change as soon as nitrites get near the 5ppm range. I continue to add 1ppm or ammonia a day. Once nitrite is decreasing on it's own I increase the dose to 2ppm of ammonia per day.

 

[verochloeedgar]

I have exactly the same problem and I at week 6 of cycling! Ammonia disappears very quickly, nitrites and nitrates are always high. I did 2 o 3 partial 60% water changes and I continue to add ammonia as I understood that was the way. I also added some fish food. I heard on some YouTube videos that 50% of the bacteria population dies after 24h without ammonia but I don't know if it is true. Hopefully someone with more experience can help us!

I just left the thank at 0 ammonia, 5nitrites and 80 nitrates without adding any more ammonia for 24 hours and my nitrites have come down to 0.25! This is week 6 of cycling and I had had nitrites and nitrates high for 2 weeks or so and I kept adding ammonia to 4ppm. I guess I was over passing the capacity of the filter to transform such a high level of nitrites to nitrates. I have done 90% pwc and I will retest in a few hours before doing a final ammonia<nitrites<nitrates. Hopefully I am fully cycled now!!! Good luck to you too!

 

[andy.keeper]

I read in a book that it's better to cycle with a couple of fish present as they create a small amount of ammonia to keep the nitrites and nitrates going enough to create a good colony on the filter media

 

[Kishore]

Test your water every day while cycling. You should dose Ammonia back up to 4 ppm everyday once it has begun to decrease. Also, add crushed fish food every 4-5 days. This ensures that the bacteria gets its micro nutrients. I followed this and got my tank cycling 2 months ago. I hope it works for you too!

 

[verochloeedgar]

I read in a book that it's better to cycle with a couple of fish present as they create a small amount of ammonia to keep the nitrites and nitrates going enough to create a good colony on the filter media

I think that is very old school and no longer recommended as it is very bad and stressful for the fish

 

[dalto]

Test your water every day while cycling. You should dose Ammonia back up to 4 ppm everyday once it has begun to decrease. Also, add crushed fish food every 4-5 days. This ensures that the bacteria gets its micro nutrients. I followed this and got my tank cycling 2 months ago. I hope it works for you too!

Nothing wrong with dosing back to 4ppm but it is probably more than is really needed and if you are in a situation like the first two posters are where their nitrites are spiking heavily I would recommend dosing less ammonia until the cycle starts to catch up.

I think that is very old school and no longer recommended as it is very bad and stressful for the fish

Done correctly, a fish-in cycle can be safe for the fish. It just requires a small relative bio-load and regular testing and water changes.

The problem is most people don't do it in a way that is safe for the fish.

 

[Wings_fan]

Still seeing fairly high nitrites. This has been going on 8 weeks now. I haven't been dosing ammonia every day, I go for every other day now, because it just increases the nitrites and then I have to change the water. Ammonia still processes fine. I started using stability last week and added some food flakes to the tank. Maybe that will help...

Test results are from this morning.

 

[Upstate TBarbs]

I'm about 3 weeks into the fishless cycle as well. My tank is a 54 gallon corner unit. I started the tank with 4 PPM ammonia. I still have ammonia at about 2 PPM, it has never gone down to 0 PPM, but nitrItes yesterday were at 0.50 PPM,and Nitr8s were about 10 PPM.

Once I saw the NitrItes start a couple days ago, I started adding 5 drops (a vague measurement, I know) of 10% Ammonium Hydroxide. I guess i keep doing this until I start to see the NitrItes drop to 0 PPM, is that right?

 

[Wings_fan]

That's the process as far as I understand it. Be sure not to let the ammonia get too high. I believe it can kill what's already there if it does. I have seen a few recommendations to add fish flakes to help the nitrite converting bacteria because of phosphorus I believe. I think that's why mine has been sitting in the nitrite phase for 7 weeks...

When I started with mine, I started with 4 ppm ammonia, but once the nitrite showed up, everyone said not to dose so high. It just converts to nitrite and then the nitrites are high, which means you need to change water to get them lower so they don't stall the cycle. And I don't know about you, but after 8 weeks it's frustrating to have to do large water changes on a 65g tank that doesn't have fish.

 

[Mpwallace1]

I read in a book that it's better to cycle with a couple of fish present as they create a small amount of ammonia to keep the nitrites and nitrates going enough to create a good colony on the filter media

I am new to the hobby. About 7 months ago I tried a fish-less cycle, and tried and tried for 6 weeks and got no where. I finally said that's it. I went out and bought 2 small dwarf powder blues, and about 2 weeks later, I started to get some good numbers. If you monitor closely and react quickly( like it appears OP does) I would think one should be able to pull it off.
Powder blues, (almost full grown now)their tank mates, and the tank are doing well.

 

[dalto]

I'm about 3 weeks into the fishless cycle as well. My tank is a 54 gallon corner unit. I started the tank with 4 PPM ammonia. I still have ammonia at about 2 PPM, it has never gone down to 0 PPM, but nitrItes yesterday were at 0.50 PPM,and Nitr8s were about 10 PPM.

Once I saw the NitrItes start a couple days ago, I started adding 5 drops (a vague measurement, I know) of 10% Ammonium Hydroxide. I guess i keep doing this until I start to see the NitrItes drop to 0 PPM, is that right?

If your ammonia isn't 0 there is no need to add more ammonia. Only add more when it reaches 0.

 

[Wings_fan]

I have been considering switching to a few fish as well. Just to see if it could finish up because it looks like something is missing.

 

[Upstate TBarbs]

If your ammonia isn't 0 there is no need to add more ammonia. Only add more when it reaches 0.

So I don't have to maintain approximately 4 PPM ammonia? I thought this was to establish a bigger bacteria colony, until they can manage to neutralize the 4 PPM in 24 hours.

 

[Upstate TBarbs]

I have been considering switching to a few fish as well. Just to see if it could finish up because it looks like something is missing.

I was thinking of putting in 3 otocinclus to take care of the algae that has started to grow.

 

[dalto]

I was thinking of putting in 3 otocinclus to take care of the algae that has started to grow.

otos would not be my first choice for a tank which is not fully cycled. They can be fragile.

What else are you planning on keeping?

 

[dalto]

So I don't have to maintain approximately 4 PPM ammonia? I thought this was to establish a bigger bacteria colony, until they can manage to neutralize the 4 PPM in 24 hours.

There isn't really a single right answer here.

First, it depends what you are putting in the tank right away. If you are loading up with a big load of fish all at once then, yes, 4-5ppm is an appropriate target amount. If you are planning to add fish more incrementally then 1-2ppm is fine.

Next you need to decide how to get there. When fishless cycling with pure ammonia I find that I almost always end up with a big nitrite spike. To lessen the impact of that spike I start with 3-5ppm of ammonia. Once it reaches 0ppm I dose back to 1ppm every time it hits 0. After a while, this is daily. Once the nitrites spike starts to decline I increase the amount of ammonia at the end to whatever my target is, in your case, 4ppm. This usually only takes a few days. I increase the ammonia at the end to avoid the huge nitrite spike that comes from continually adding large amounts of ammonia when the bacteria colonies which consume the nitrites have not developed as much as the ones consuming the ammonia.

An alternative, but equally valid, approach is to dose back to 4ppm every day. The advantage to this approach is that there is no ramp period at the end of the cycle. The only problem is that if you do hit a nitrite spike, you are converting tons of ammonia to nitrite every day which then forces water changes.

For me, the long nitrite spike seems to only happen when I use ammonia directly. When using ammonia directly I see the ammonia get consumed fairly quickly and then nitrite hang around forever. In a fish-in cycle I usually see the opposite, the ammonia hanging around forever and then a brief spike in nitrites which quickly goes away.

Generally, the total amount of time is the same either way, 6-8 weeks. Since I am impatient, I usually cheat and use bacteria additives.

 

[Upstate TBarbs]

What else are you planning on keeping?

A tank of assorted tiger barbs, 3 (?) albino corys, and 3 (?) otos.

 

[dalto]

A tank of assorted tiger barbs, 3 (?) albino corys, and 3 (?) otos.

Of those, a tiger barb would be best the choice if you want to finish the cycle with fish.

Do a 100% water change shortly before adding the fish. It probably goes without saying but you also need to stop dosing ammonia.

Keep an eye on nitrite. Do you know what your ph is?