Has my tank finished cycling?

[Kris33]

G’Day All,

I’m new here and new to marine tanks.

I’ve been cycling my tank for three weeks now. My set up in an all in one 30 gallon tank with sand and caribsea life rock and biosphere media. I started the cycle with some fish food but after a visit to my LFS they prompted me to add a sliver of prawn to the tank. And I’m using Aquaforest Bio S. I’ve been testing with Salifert and have really struggled to read the ammonia vials. They were always cloudy with slight yellow tinge, but hard to compare to the colour chart.

These are my test readings from today:
NH3: 0.15-0.25 Cloudy
NO2: 0.2 (from side)
NO3: 25 (from top)

I took a sample of my water today to the LFS and they returned the following results:
NH3: 0.2
NO2: 0.5
NO3: 0
PH: 8
Alk: 8.7

I’m a bit confused how the LFS returned a zero for nitrate as my readings for it have been increasing over the past three weeks. The LFS said that the bacteria take down NO3 and hence why it’s zero. But all of my research had me thinking that NO3 increases and that their levels were controlled via water changes, etc.

Can anyone explain the discrepancy between my Salifert result and the LFS?

Is the LFS correct in saying that zero nitrate would be expected in a cycled tank (despite no water changes yet)?

The LFS recommended a 10% water change and it would pretty much be good to go - does that sound right?

Is the cycle complete?

 

[twentyleagues]

I would say there is a discrepancy in testing. Either they messed up the n03 or you have. N03 can be used by bacteria but it takes quite a while and the correct conditions to cultivate that bacteria. Algaes also use N03. You are correct however that most of the N03 is exported via water change. Depending on the test method used and kit N03 is pretty easy to mess up. Api tests are probably the easiest ones to get wrong. That second test solution is incredibly easy to mess up as components tend to drop out of solution and really need a lot of agitation to get back into solution.
If you do have N03 that means the cycle is happening! Ammonia tests can be hard to discern also.
What test are you using and what test is the lfs using?

 

[Rmckoy]

G’Day All,

I’m new here and new to marine tanks.

I’ve been cycling my tank for three weeks now. My set up in an all in one 30 gallon tank with sand and caribsea life rock and biosphere media. I started the cycle with some fish food but after a visit to my LFS they prompted me to add a sliver of prawn to the tank. And I’m using Aquaforest Bio S. I’ve been testing with Salifert and have really struggled to read the ammonia vials. They were always cloudy with slight yellow tinge, but hard to compare to the colour chart.

These are my test readings from today:
NH3: 0.15-0.25 Cloudy
NO2: 0.2 (from side)
NO3: 25 (from top)

I took a sample of my water today to the LFS and they returned the following results:
NH3: 0.2
NO2: 0.5
NO3: 0
PH: 8
Alk: 8.7

I’m a bit confused how the LFS returned a zero for nitrate as my readings for it have been increasing over the past three weeks. The LFS said that the bacteria take down NO3 and hence why it’s zero. But all of my research had me thinking that NO3 increases and that their levels were controlled via water changes, etc.

Can anyone explain the discrepancy between my Salifert result and the LFS?

Is the LFS correct in saying that zero nitrate would be expected in a cycled tank (despite no water changes yet)?

The LFS recommended a 10% water change and it would pretty much be good to go - does that sound right?

Is the cycle complete?

Cycle science guru

@brandon429
Has the exact answer you’re looking for

 

[Kris33]

I would say there is a discrepancy in testing. Either they messed up the n03 or you have. N03 can be used by bacteria but it takes quite a while and the correct conditions to cultivate that bacteria. Algaes also use N03. You are correct however that most of the N03 is exported via water change. Depending on the test method used and kit N03 is pretty easy to mess up. Api tests are probably the easiest ones to get wrong. That second test solution is incredibly easy to mess up as components tend to drop out of solution and really need a lot of agitation to get back into solution.
If you do have N03 that means the cycle is happening! Ammonia tests can be hard to discern also.
What test are you using and what test is the lfs using?

Thanks for your response and insight into potential issues with the test kits.

I’m using Salifert test kits. And my nitrate readings have been gradually increasing. A couple of days ago it was at 5 and the 25 reading from today is the largest reading so far, so I had assumed the cycle was happening.

The LFS had a digital tester which tested multiple parameters at one time. I’ll attach a photo. This was actually the second set of test results that the LFS did as the first one they did returned 0 Alk.

 

[Cell]

Given the way our nitrite test kits work, having 0.5 nitrite but 0 nitrate does not make sense.

 

[twentyleagues]

Thanks for your response and insight into potential issues with the test kits.

I’m using Salifert test kits. And my nitrate readings have been gradually increasing. A couple of days ago it was at 5 and the 25 reading from today is the largest reading so far, so I had assumed the cycle was happening.

The LFS had a digital tester which tested multiple parameters at one time. I’ll attach a photo. This was actually the second set of test results that the LFS did as the first one they did returned 0 Alk.

With that info id guess the 0 nitrate reading is also incorrect. Salifert are good test kits I have used them and still do. I also use api and hannah. If I get a weird reading ill use a different test to double check, Ill also periodically take a sample to my lfs and have them test but they use the same tests I do.

 

[Kris33]

Given the way our nitrite test kits work, having 0.5 nitrite but 0 nitrate does not make sense.

Yes, that’s what I couldn’t understand. It just didn’t make sense to me.

Hmm, so I guess I can’t take what the LFS said as gospel and hence a water change won’t get my ammonia and nitrite down enough to be ready for fish?

 

[Kris33]

With that info id guess the 0 nitrate reading is also incorrect. Salifert are good test kits I have used them and still do. I also use api and hannah. If I get a weird reading ill use a different test to double check, Ill also periodically take a sample to my lfs and have them test but they use the same tests I do.

What is funny is that I took the water sample to the LFS for a second opinion as I had no idea if I had ammonia.

But the ammonia reading at the LFS is comparable to my Salifert result. I.e. slight yellow tinge to the cloudy water. Is it meant to be cloudy?

 

[twentyleagues]

Ive had cloudy with what was seen to be 0 ammonia on hannah tests, but cloudy usually mean there is ammonia from my experience.

 

[brandon429]

The reason you don't need more testing is because there aren't any cycling charts with a three week ammonia control line. Ammonia is the only parameter that factors in updated cycling science for searchable reasons on the site: nitrite is chemically neutral in reefing, nitrate doesn't factor because hundreds of fully cycled reefs here run zero nitrate

You're done cycling because this is the same thing as a shrimp cycle and they're done at three weeks wait time. The wait time is your measure, not the cheap test kits. You can't make your tank safer for fish by waiting longer, you must now move from cycling concerns into fish disease prevention planning from the disease forum: fallow and quarantine.

You're at this stage now, be sure and read this thread:

Has anyone done coral/inverts only and no fish at first?

Fish seem to be the main cause of disruption in a display tank, given the current circumstances in the hobby with pests (ich, velvet, parasites, etc.). I have been in this hobby for 18 years, and the amount of pests that are showing up lately is much more (could also be the fact that we have...

www.reef2reef.com

 

[Kris33]

Ive had cloudy with what was seen to be 0 ammonia on hannah tests, but cloudy usually mean there is ammonia from my experience.

Thanks for your help with this. Looks like the zero reading on nitrate at the LFS was wrong. I’ve done a decent water change in an attempt to reduce the ammonia.