Slow Nitrogen Cycle

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Started my first tank (75 gal) 6 weeks ago. Planned to use TBS ultra live sand to do the heavy lifting of the nitrogen cycle, more or less following the serious reefs 90/10 method. Unfortunately I was out of town for the next 2 delivery dates for TBS so I had to wait a month. I decided to cycle the tank with ammonium chloride and microbacter 7 from my LFS. Ammonia probably peaked around 1.5 to start.

After 3 weeks my ammonia was still 0.75, nitrites always testing zero (api test kit failure maybe?), and nitrates were beginning to show up on the Hanna checker. At this point I dosed 4 of of Dr Tim’s to try and speed things along in preparation for my live sand delivery.

Another week later I’m seeing very minimal progress on the ammonia per API test kits done by myself and LFS. There were both nitrites (this time measured on a test strip at an LFS) and nitrates present so things were definitely happening but slowly. I probably should have cancelled my TBS order but it was too late so I did a 25 gal water change, added some seachem prime, and added 24 lbs of tbs sand the next day.

Fast forward to today (1 week post TBS sand and 6 weeks after initial ammonium chloride dose) and I’m still getting 0.25-0.5 ammonia, minimal to no nitrites and, curiously, zero nitrates. I assume something in the live sand consumed the nitrates like algae or anaerobic bacteria…? I’m dosing prime daily in an attempt to protect the hitchhikers. I have multiple cerith snails and a bivalve mollusk that seem to be doing great.

If I could do it over again I would have waited even longer for the tbs sand but too late now. Any ideas how to complete this cycle or why it’s taking so long? Maybe 6 weeks isn’t unusual? I was thinking about trying Fritz turbo start but not sure if there are risks in adding what will be the 3rd bottled bacteria product 🤦‍♂️.
 
Started my first tank (75 gal) 6 weeks ago. Planned to use TBS ultra live sand to do the heavy lifting of the nitrogen cycle, more or less following the serious reefs 90/10 method. Unfortunately I was out of town for the next 2 delivery dates for TBS so I had to wait a month. I decided to cycle the tank with ammonium chloride and microbacter 7 from my LFS. Ammonia probably peaked around 1.5 to start.

After 3 weeks my ammonia was still 0.75, nitrites always testing zero (api test kit failure maybe?), and nitrates were beginning to show up on the Hanna checker.
This can't happen unless the tank is cycled, or unless you are dosing nitrates.

Everything else is just noise from the test kits, which have a reputation for not ever showing zero ammonia.

At this point I dosed 4 of of Dr Tim’s to try and speed things along in preparation for my live sand delivery.

Another week later I’m seeing very minimal progress on the ammonia per API test kits done by myself and LFS. There were both nitrites (this time measured on a test strip at an LFS) and nitrates present so things were definitely happening but slowly. I probably should have cancelled my TBS order but it was too late so I did a 25 gal water change, added some seachem prime, and added 24 lbs of tbs sand the next day.
Prime, I think that it causes additional noise in hobby testing kits, and may do nothing in marine environments?
@Randy Holmes-Farley - I'm probably confused, but I still believe that your tank was cycled weeks ago.
Fast forward to today (1 week post TBS sand and 6 weeks after initial ammonium chloride dose) and I’m still getting 0.25-0.5 ammonia, minimal to no nitrites and, curiously, zero nitrates. I assume something in the live sand consumed the nitrates like algae or anaerobic bacteria…? I’m dosing prime daily in an attempt to protect the hitchhikers. I have multiple cerith snails and a bivalve mollusk that seem to be doing great.

"If I could do it over again I would have waited even longer"
i appreciate your dilegence but if you are waiting for an API test kit to give you a zero in ammonia, it may never happen. Never is a long time from now, and you are three weeks past cycled, at least.
for the tbs sand but too late now. Any ideas how to complete this cycle or why it’s taking so long? Maybe 6 weeks isn’t unusual? I was thinking about trying Fritz turbo start but not sure if there are risks in adding what will be the 3rd bottled bacteria product 🤦‍♂️.
Don't buy more magic bugs, elixers, or biomatrixes or other fixes for a problem that is only related to the hobby test kits and errors they contain.

This tank is cycled. Add fish slow, and feed lightly because that's the way to ramp up safely with new tanks. GL

happy jim carrey GIF by O&O, Inc

This tank is clear! 😂
 
This can't happen unless the tank is cycled, or unless you are dosing nitrates.

Everything else is just noise from the test kits, which have a reputation for not ever showing zero ammonia.


Prime, I think that it causes additional noise in hobby testing kits, and may do nothing in marine environments?
@Randy Holmes-Farley - I'm probably confused, but I still believe that your tank was cycled weeks ago.

i appreciate your dilegence but if you are waiting for an API test kit to give you a zero in ammonia, it may never happen. Never is a long time from now, and you are three weeks past cycled, at least.

Don't buy more magic bugs, elixers, or biomatrixes or other fixes for a problem that is only related to the hobby test kits and errors they contain.

This tank is cycled. Add fish slow, and feed lightly because that's the way to ramp up safely with new tanks. GL

happy jim carrey GIF by O&O, Inc

This tank is clear! 😂
I hope this is the case however when I have had the water tested at a few different LFS they also have tested positive ammonia while their own tank water tested at zero as a comparison.
 
I hope this is the case however when I have had the water tested at a few different LFS they also have tested positive ammonia while their own tank water tested at zero as a comparison.
Are you still adding ammonia? YOu mentioned that you added "4", which I think would guess was 4 drops per gallon, or 4 ppm? If you raised it too high that might be a source of any problem?
 
I hope this is the case however when I have had the water tested at a few different LFS they also have tested positive ammonia while their own tank water tested at zero as a comparison.
What do you mean by "positive ammonia"? If that's like 0.25 ppm, that's nothing to worry about, and I'd move forward 🙂
 
I re-read your top post, and if I follow you, you're fine 🙂

Relax. Stop adding Prime, it DOES NOT do anything for ammonia anyway, and *might* be interfering with your testing. This has been tested here (and elsewhere):
https://www.reef2reef.com/threads/does-prime-actually-detoxify-free-ammonia-nh3.849985/

With the TBS live sand, you're in great shape. You may be getting a bit of a 'mini-cycle', but it's nothing to worry about. The critters can handle it. I wouldn't be concerned unless the animals seem visibly distresed, and there's no other causes.

Are you getting TBS rock and do you have a date for delivery yet?
 
What do you mean by "positive ammonia"? If that's like 0.25 ppm, that's nothing to worry about, and I'd move forward
Just that each time I compared my test with the LFS, they came up about the same. My water would turn green, theirs would be a convincing yellow or zero.
 
I re-read your top post, and if I follow you, you're fine 🙂

Relax. Stop adding Prime, it DOES NOT do anything for ammonia anyway, and *might* be interfering with your testing. This has been tested here (and elsewhere):
https://www.reef2reef.com/threads/does-prime-actually-detoxify-free-ammonia-nh3.849985/

With the TBS live sand, you're in great shape. You may be getting a bit of a 'mini-cycle', but it's nothing to worry about. The critters can handle it. I wouldn't be concerned unless the animals seem visibly distresed, and there's no other causes.

Are you getting TBS rock and do you have a date for delivery yet?
I don’t have plans for live rock currently. The serious reefs method calls for live sand rather than rock to decrease chances of unwanted hitchhikers. I don’t have a strong opinion on that though and could possibly be convinced to add some later
 

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