Cycling Confusion

fernalfer

New member
Ok i have a 120 gallon tank i'm cycling with Marco Completely Dry Rock and CaribSea Live sand. I'm doing the fishless cycle method dosing pure ammonia. Now i initially dosed 4 ppm ammonia and Fritzzyme 9 nitrifying bacteria it took about 3 days to bring that to 0. At that point i tested for Nitrites and they were through the roof. I have the Red Sea Test kit and it was darker then the darkest color. Not sure the number because the Red sea kits only go to 1.

I have dosed 3.5ppm ammonia a second time and it took 36 hours to get to 0. Nitrites still through the roof. Nitrates thru the roof

Now i get mixed opinions on how to proceed. Some say stop dosing ammonia because it will make my nitrates higher in the end and let it cycle naturally from here on out. **Problem i see with that is how i'm supposed to see when my bacteria has built up enough to convert my ammonia in under 12hrs? Also don't you have to keep bacteria fed with some kind of ammonia source?

And some say to continually dose up to 4ppm until it can convert it in under 12hrs. then scale back on the ammonia dosage.

I'm at 0 for ammonia right now and unsure which route to take.
 
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No more ammonia. Those bacteria are good and fed. They'll be fine. Let the nitrite eating bacteria propogate. It can take some time. I used dry rock and live sand, and my cycle took 6 weeks. Gotta just be patient. But you don't need any more ammonia. Once nitrite has zeroed out, you can test it with a bit of ammonia to see if both zero out to confirm you are cycled. But for now it's just a waiting game.
 
No more ammonia. Those bacteria are good and fed. They'll be fine. Let the nitrite eating bacteria propogate. It can take some time. I used dry rock and live sand, and my cycle took 6 weeks. Gotta just be patient. But you don't need any more ammonia. Once nitrite has zeroed out, you can test it with a bit of ammonia to see if both zero out to confirm you are cycled. But for now it's just a waiting game.

Ok so i do not need to be worried of the bacteria that has now colonized from my initial dosing of ammonia will die off? It is ok to just leave as is now with no more ammonia dosing? Just wait now for my Nitrite levels to lower to zero?
 
On another forum i got an answer like this:

your sand is making the results skew, its live so its mimicking what cycled live rock does. all you need to do is go off the known cycling time frames for dry rock, 40 days underwater in the presence of anything living will xfer enough that you can simply start with a low bioload after 40 days submersion because your sand had some ability inherent from day 1, and the extra time allowed the rocks to build up.

since your sand oxidizes some of the free ammonia you add, its not required to be precise while it ages for a month, just keep adding some ammonia, and some bac in addition to whats there, I guarantee you w be good to go in a month for a light start bioload.

You do not ever have to test nitrite nor factor it in your marine tank cycle, that step above is unnecessary and adds to complete cycling confusion because it doesn't state which test kits to use, which ones to avoid, and how even fully matured reefs can spike a little nitrite just by moving the rocks around in the tank...or dosing prime...lots of reasons. skip nitrite testing, go off what ammonia does.

after 30-40 days if you digest 3 ppm to zero in 24 hours you simply begin light reefing.

You could begin some now, due to the power and surface area of your live sand, but no need to push it. when the rock catches up the tank will have powerful filtration capabilities.
 
I'm not sure how to make it any clearer to you than I already did, stop dosing ammonia. If the bacteria in your live sand processed the ammonia, great (although I highly doubt it)! What processed the ammonia was the bacteria you added, end of story. Your high levels of nitrites alone is proof that the bacteria is processing ammonia into nitrites. Very high levels of nitrites will slow down the process of building up the bacteria that converts the nitrites into nitrates. If you insist on following incorrect advice expect your nitrite to continue to climb and delay the cycle.
 
I'm not sure how to make it any clearer to you than I already did, stop dosing ammonia. If the bacteria in your live sand processed the ammonia, great (although I highly doubt it)! What processed the ammonia was the bacteria you added, end of story. Your high levels of nitrites alone is proof that the bacteria is processing ammonia into nitrites. Very high levels of nitrites will slow down the process of building up the bacteria that converts the nitrites into nitrates. If you insist on following incorrect advice expect your nitrite to continue to climb and delay the cycle.

Ok the dosing of ammonia will stop. Thanks. I wish my red Sea Kit went higher then 1 for my nitrite reading so i could actually see what the true reading is.
 
Ok the dosing of ammonia will stop. Thanks. I wish my red Sea Kit went higher then 1 for my nitrite reading so i could actually see what the true reading is.

Normally API tests aren't the greatest. But I think their Nitrite one is actually pretty good. I haven't heard many bad things about it. Their Nitrate test however, is crap.
 
Normally API tests aren't the greatest. But I think their Nitrite one is actually pretty good. I haven't heard many bad things about it. Their Nitrate test however, is crap.

I think my buddy has the API test kit for nitrites, maybe i can borrow a few from him so i can see how high my nitrites truly are.
 
Cycling Confusion

Ok the dosing of ammonia will stop. Thanks. I wish my red Sea Kit went higher then 1 for my nitrite reading so i could actually see what the true reading is.



It does. There are instructions for high range. At least in the pro tests kits there are.

Edit: here it is

Nitrate Test "“ directions for use
1. Usingthesyringeprovided,placeexactly5mlofthewatertobetestedinto the glass vial.
2. Add 5 drops of NO2/NO3 reagent A, close the vial with the cap and shake for 10 seconds.
3. AddaleveledmeasuringspoonofNO3ReagentB,closethevialwiththecap and shake vigorously for 60 seconds.
4. AddaleveledmeasuringspoonofNO2/NO3ReagentC,closethevialwiththe cap and shake vigorously for 10 seconds.
5. Wait9minutesforthecolorinthevialtostabilize.
6. Removethecapfromthereactionvialandshakethevialgentlytorelease
tiny air bubbles and reagent particles that settled on the bottom.
7. MovethevialbetweenthedesignatedpositionsontheNitratecolorcard,
look into the vial from above and compare the color in the vial to the colors on the card. Choose the Nitrate level that gives the closest color match and if necessary estimate an intermediate value. The color is stable for 2 minutes.
High Range: For levels of Nitrate above 50 ppm dilute 1 ml of the water to be tested with 4 ml of RO water. Multiply the result by 5 for true nitrate level.
 
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Also I'm fairly certain the bacteria that process the ammonia can go dormant for some time like a year or so without any ammonia. I wouldn't keep putting ammonia in. Good luck
 
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