Is my cycle done?

grisban

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So im 30 days in my cycle and my ammonia is 0 ppm. My nitrites are off the chart but I read that for reeftanks nitrite / nitrates are not toxic for fish anyways. Should i wait for my first fish till nitrite is 0? Should i waterchange and get my first fish?

I used the old school shrimp method to kick off my ammonia spike so i cant really do the 2 ppm 24h check
 

JTP424

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Have nitrates started showing up yet?
 

jma97

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If ammonia is 0 and you are consistently reading nitrates, then probably cycled to go especially if it's been 30 days. Did you add anything to the tank (e.g., bottled bacteria)? Assuming you started with dry rock and not live rock from a LFS. If you can't do the check with pure ammonia, try adding a source of ammonia into the tank like some fish food and doing a reading 24 h later. Should help you tell if your bio filter is processing ammonia.

A tank is generally cycled when it is reading no ammonia with the presence of nitrates.
 
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grisban

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If ammonia is 0 and you are consistently reading nitrates, then probably cycled to go especially if it's been 30 days. Did you add anything to the tank (e.g., bottled bacteria)? Assuming you started with dry rock and not live rock from a LFS. If you can't do the check with pure ammonia, try adding a source of ammonia into the tank like some fish food and doing a reading 24 h later. Should help you tell if your bio filter is processing ammonia.

A tank is generally cycled when it is reading no ammonia with the presence of nitrates.
Yep i added bottled bacteria and nitrates are present
 

jma97

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Given the time frame, addition of bottled bacteria, and your current parameters, should be cycled IMO
 

nickynels

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I’m pretty sure nitrites are still toxic, but you may have to wait one or two more weeks… That’s how my aquarium was.
 

Fish Fan

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I’m pretty sure nitrites are still toxic, but you may have to wait one or two more weeks… That’s how my aquarium was.
Nitrites are indeed non-toxic in saltwater, unlike in freshwater 🙂 Please see this post from Randy Holmes-Farley, and the link to his article on nitrite toxicity:
 

CaseyC33

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Hi all,

Want to piggy back off of this without starting a new thread!

I am in a similar situation and have some questions. I have been cycling around 1.5/2 weeks a fluval 13.5 evo. I used fritz powdered ammonia and fritz bb and dosed to 2ppm ammonia. I have been monitorring the ammonia and have seen a gradual decline to what is now 0ppm ammonia.

I similarly have read that nitrites are less of a concern to saltwater than freshwater and have a reading of 2ppm nitrite. I have presence of nitrates as well. I will WC those down if needed before adding fish.

My main question, at what point should I add fish so that I do not lose my cycling without a presence of ammonia feeding the cycle. I was going to do two clowns and eventually a goby/pistol shrimp.

Fish can go in as soon as today or tomorrow.

Thanks!

Casey
 

ScottJ

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Hi all,

Want to piggy back off of this without starting a new thread!

I am in a similar situation and have some questions. I have been cycling around 1.5/2 weeks a fluval 13.5 evo. I used fritz powdered ammonia and fritz bb and dosed to 2ppm ammonia. I have been monitorring the ammonia and have seen a gradual decline to what is now 0ppm ammonia.

I similarly have read that nitrites are less of a concern to saltwater than freshwater and have a reading of 2ppm nitrite. I have presence of nitrates as well. I will WC those down if needed before adding fish.

My main question, at what point should I add fish so that I do not lose my cycling without a presence of ammonia feeding the cycle. I was going to do two clowns and eventually a goby/pistol shrimp.

Fish can go in as soon as today or tomorrow.

Thanks!

Casey
Dry rock? If you have 0 ammonia and nitrates, you are good. You can confirm by adding ammonia to 2ppm and testing the next day. If it tests 0ppm, you are good to go.

However, one and a half weeks seems pretty short, but 2 weeks should be ok. What exactly are you reading for nitrates?

Lots of good info here;
The Supreme Guide To Setting Up A Saltwater Reef Aquarium | Reef2Reef
 

Tahoe61

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Hi all,

Want to piggy back off of this without starting a new thread!

I am in a similar situation and have some questions. I have been cycling around 1.5/2 weeks a fluval 13.5 evo. I used fritz powdered ammonia and fritz bb and dosed to 2ppm ammonia. I have been monitorring the ammonia and have seen a gradual decline to what is now 0ppm ammonia.

I similarly have read that nitrites are less of a concern to saltwater than freshwater and have a reading of 2ppm nitrite. I have presence of nitrates as well. I will WC those down if needed before adding fish.

My main question, at what point should I add fish so that I do not lose my cycling without a presence of ammonia feeding the cycle. I was going to do two clowns and eventually a goby/pistol shrimp.

Fish can go in as soon as today or tomorrow.

Thanks!

Casey
I would be reluctant to suggest a system set up with dry rock is cycled at 2 weeks.
If you can add some live wet rock that would be ideal.
I would not worry about losing the cycle. Bacteria are going to spread regardless. You could also try add a small pinch of fish food.

Honestly my suggestion is to wait at least another week before adding livestock. You don't want to join the my clowns have ich or Brooklynella and are sympathetic because I add them to a new tank too quickly club.

Congratulations on your new tank.
 

CaseyC33

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Dry rock? If you have 0 ammonia and nitrates, you are good. You can confirm by adding ammonia to 2ppm and testing the next day. If it tests 0ppm, you are good to go.

However, one and a half weeks seems pretty short, but 2 weeks should be ok. What exactly are you reading for nitrates?

Lots of good info here;
The Supreme Guide To Setting Up A Saltwater Reef Aquarium | Reef2Reef
Dry rock and 20lbs live sand.

I does BB and added fish food 3/24 and dosed to 2ppm ammonia on 3/25 (when the fritz ammonia was delivered.) I have been adding fritz BB everyday too.

Nitrates reading 80 ppm with the API master test kit.

The ugly stage has startedm, if that's any indication of anything! lol
 

ScottJ

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Dry rock? If you have 0 ammonia and nitrates, you are good. You can confirm by adding ammonia to 2ppm and testing the next day. If it tests 0ppm, you are good to go.

However, one and a half weeks seems pretty short, but 2 weeks should be ok. What exactly are you reading for nitrates?

Lots of good info here;
The Supreme Guide To Setting Up A Saltwater Reef Aquarium | Reef2Reef
Dry rock and 20lbs live sand.

I does BB and added fish food 3/24 and dosed to 2ppm ammonia on 3/25 (when the fritz ammonia was delivered.) I have been adding fritz BB everyday too.

Nitrates reading 80 ppm with the API master test kit.

The ugly stage has startedm, if that's any indication of anything! lol
It certainly won't hurt to wait another week. A water change if you have 80 parts per million nitrate would be a good idea. Since it's such a small volume I would do a big water change.

For what it's worth, strictly in my opinion, I think you maxed out with a pair of clowns in that tank. And only because of the small space they may not tolerate a goby, even though they stay on the sand. It's a pretty small tank for a pair of clowns. A single clown and a Gobi woodwork fine. I used to run that tank with a single clown and a tail spot blenny. They were good together. It's strictly my opinion. You do you.
 

CaseyC33

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I appreciate the feedback. I would likely do a yasha goby and pistol shrimp. Hopefully staying on the sand and under the rock will quell any aggression.

I will likely upgrade to a 29 at somepoint, so I would get the clowns small. I just moved to a new state and had the itch to get something up!

I’ve had a 40B in the past, but it’s been a while since I’ve done a cycle like this.
 

Randy Holmes-Farley

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Hi all,

Want to piggy back off of this without starting a new thread!

I am in a similar situation and have some questions. I have been cycling around 1.5/2 weeks a fluval 13.5 evo. I used fritz powdered ammonia and fritz bb and dosed to 2ppm ammonia. I have been monitorring the ammonia and have seen a gradual decline to what is now 0ppm ammonia.

I similarly have read that nitrites are less of a concern to saltwater than freshwater and have a reading of 2ppm nitrite. I have presence of nitrates as well. I will WC those down if needed before adding fish.

My main question, at what point should I add fish so that I do not lose my cycling without a presence of ammonia feeding the cycle. I was going to do two clowns and eventually a goby/pistol shrimp.

Fish can go in as soon as today or tomorrow.

Thanks!

Casey

You are adequately cycled for a fish and do not have high nitrate, maybe not any nitrate. The nitrite will give a false high nitrate reading.
 

ScottJ

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You are adequately cycled for a fish and do not have high nitrate, maybe not any nitrate. The nitrite will give a false high nitrate reading.
Yup, my mistake... I missed the nitrite reading 🙃

Randy, do you think in a case like this it would be a good idea to do a water change before adding fish? (I could be wrong, but I always think water changes aren't a bad thing)
 

Fish Fan

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Yup, my mistake... I missed the nitrite reading 🙃

Randy, do you think in a case like this it would be a good idea to do a water change before adding fish? (I could be wrong, but I always think water changes aren't a bad thing)
I'm not Randy, and I certainly don't speak for him, but I'll stick my nose in here anyway 🤪

In my humble opinion, it's never a bad idea to do a water change. The only negatives are the work and the cost.

That said, I don't think the standard advise to do a large water change after a fish-less cycle is necessary. Many times the cycling tank still has nitrite, which as Randy notes will affect testing for nitrate, and for that reason you don't really know what your nitrate concentration is until all the nitrite has zeroed out. For this reason, I'm not so sure that doing a large water change is a necessary component of a fish-less cycle, but I'd certainly be interested in Randy's take on this.

Furthermore, many (most?) new reefers are set on getting their tank cycled so they can add their Clownfish, and Clownfish don't care at all if nitrate is high, from my experience 🙂
 

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Yup, my mistake... I missed the nitrite reading 🙃

Randy, do you think in a case like this it would be a good idea to do a water change before adding fish? (I could be wrong, but I always think water changes aren't a bad thing)
I'm not Randy, and I certainly don't speak for him, but I'll stick my nose in here anyway 🤪

In my humble opinion, it's never a bad idea to do a water change. The only negatives are the work and the cost.

That said, I don't think the standard advise to do a large water change after a fish-less cycle is necessary. Many times the cycling tank still has nitrite, which as Randy notes will affect testing for nitrate, and for that reason you don't really know what your nitrate concentration is until all the nitrite has zeroed out. For this reason, I'm not so sure that doing a large water change is a necessary component of a fish-less cycle, but I'd certainly be interested in Randy's take on this.

Furthermore, many (most?) new reefers are set on getting their tank cycled so they can add their Clownfish, and Clownfish don't care at all if nitrate is high, from my experience 🙂
Good points. Interesting take on the standard advice about doing a big water change after cycling. Probably isn't necessary for the fish health. But I'm in the same camp that a water change cures many ills. Plus if it's only you small tank the cost and work isn't that great. And it gets you in the mindset of maintenance right from the get-go for a new tank owner.
 

Randy Holmes-Farley

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Yup, my mistake... I missed the nitrite reading 🙃

Randy, do you think in a case like this it would be a good idea to do a water change before adding fish? (I could be wrong, but I always think water changes aren't a bad thing)

Nothing wrong with it, but I think the old mantra to do a water change after cycling is a left over from when folks wanted very low nitrate.
 

MC Blowfish

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I appreciate the feedback. I would likely do a yasha goby and pistol shrimp. Hopefully staying on the sand and under the rock will quell any aggression.

I will likely upgrade to a 29 at somepoint, so I would get the clowns small. I just moved to a new state and had the itch to get something up!

I’ve had a 40B in the past, but it’s been a while since I’ve done a cycle like this.

It's always a good idea to stick with your limit when you have the smaller tank. Just because you never know if six months down the road the plan for the larger tank falls through.
 

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