Cycling With Plants And Seeding And Bottled Bacteria

[eduller]

I promise I have read the sticky and read every post I can find about cycling with and without plants. I *think* I am doing what I should be doing and I *think* I have a grasp on this, but I wanted to confirm.
 
I'm doing a fishless, planted cycle in a 54 gallon tank. I took 1/3 of the media from each of two 10 gallon established tanks and also used a bottle of Dr. Tim's One and Only. The tank is moderately planted. I have a number of pretty fast growing plants that have visibly grown easily a couple of inches in the past week. I'm using PPS-Pro ferts and excel. I have a Finnex Ray 2 light strip along with just a shop light with a 6500k fluorescent bulb clipped to the back corner of the tank (it's a corner tank, so shaped like a slice of pie...mmm, pie...).
 
Tomorrow, I will be a week into the process. I'm using Dr. Tim's ammonia drops as my ammonia source and dosing to 3 ppm. I have been testing daily. After the first couple of days, it seems to be the trend that the plants/bacteria are taking care of about half the ammonia in a 24 hour period. I never got a nitrite reading at all, not even a blip on the test. Two nights ago, nitrate started showing at about 30ppm. Last night, no nitrite again, but nitrate was about 20ppm. I have not done any water changes. PH is a steady 7.4, temp is 78.
 
So - I'm thinking the nitrite spike happened between testing and quickly because of both the seeded media and the bottle o' bacteria. There are no nitrates in my tap water. I don't see any algae. I know both using bottled bacteria and cycling with plants throw off the whole traditional fishless cycle rules. I'm certainly not stocking the tank until it's taking care of that ammonia within 24 hours, but does it seem like I'm on the right track? I am dosing ferts according to the instructions. I am just trying to think if there is anything else that could be causing the nitrates rather than just the cycle is completing.

 

[the_lock_man]

On the face of it, yes it does look like it's going in the right direction.

 

[TwoTankAmin]

As far as I can tell you were very close to having set up an instantly cycled tank. But you did things I would not have suggested. Here is what i would have recommended as the course of action to have followed:
 
1. Set up the tank and plant it. No cycled media nor Dr Tims. No ammonia to be added at this point. Allow about 2 weeks for the plants to start to establish.
2. After 2 weeks, move the cycled media into the filters/tank and then dose the tank to 2 ppm of ammonia. Wait 24 hours and test. If you don't get  0/0 or very close, turn off the tank lights add Dr. Tims and redose ammonia in the same amount as before.
3. Test in 24 hours. You should see 0/0 for sure.
 
But consider this: The plants should handle a lot of the cycling chores and they bring in bacteria. The seeding makes things even better for cycling and likely there was 0 need for the Dr. Tims. I Have cycled a ton of tanks in various configurations. But in virtually every instance that involved both decent planting and some amount of cycled media from other tanks no tank took more than a week and many were ready for a full fish load in 24 hours or less.
 
Bear in mind that the directions for fishless cycling here are written for tanks with few or no plants and no seeding. Once these things are brought into play, that article is no longer a reasonable guide to follow. For one reason it is overly safe in terms of the amount of bacteria it seeks to develop. It is more than is needed in order to be safe. Too much nitrifying bacteria is almost never a problem, too little almost always is. Planted tanks change the pardigm, change the test readings one expects to see and allows for a lower ammonia dosing regimen. The more plants one has and the faster growing they are, the less need for bacteria (traditional cycling) there is.
 
You saw no nitrite because you had nitrite converting bacteria in the tank to start. This is the single most important factor in accelerating a cycle. I mistrust your ammonia readings and here is why. When plants take up ammonia, they do not create nitrite and they eat nitrate. When you seed bacteria you pretty much seed cycling capacity. That means whatever amount of ammonia that seeding can process it should process the amount of nitrite that ammonia creates will also be processed. If you have too little ammonia bacteria to reduce the ammonia to zero in 24 hours or less, you do not have enough nitrite bacteria to process the amount of nitrite created. the ammonia bacs reproduce faster than the nitrite ones. So for my money either you ammonia results are wrong or the nitrite ones are, and my bet is its the former/
 
The appropriate amount of Dr Tims (if it was properly handled along the way and you followed the directions) will cycle a tank in about a week. That is without any added cycled media and with no plants at all and with one or two ammonia additions. Given all you report, your tank should have been cycled in as fast as instantly and perhaps as slow as a week. Your test results for ammonia and nitrite should not be possible to obtain at the same time in your situation.
 
I distrust the nitrate tests more than any of them. Again in your tank you should have lower than expected nitrate which could even be 0 with plants.

 

[eduller]

I have another ammonia test kit I could take home and try out.
 
...I will also ask my wife if she added any ammonia or at the wrong time...I did have her do the ammonia once when I forgot to do it in the morning, and it is entirely possible that she either A) forgot to add it at that time and then randomly remembered and added it yesterday before I got home from work or B) thought she needed to add it every day (less likely). That's a good thing to investigate, I think.
 
Thank you

 

[eduller]

Okay I just ran another set of tests with the test kit I keep at work. I also found out that my wife did add ammonia yesterday, so the 3ppm reading I got last night was from freshly added ammonia.
 
Last night, the tests: ammonia 3ppm, 0 nitrite, nitrate 20ppm.
 
Just now: ammonia 1ppm, 0 nitrite, nitrate ~5ppm, maybe halfway between 5 and 10. I tested with both test kits and got the same results with both. So the way I understand it, I must have some bacteria working in order to have nitrates showing up. So assuming that to be true, there must be bacteria producing nitrites as well, but I also understand that nitrite is converted rather quickly to nitrate, so I am perhaps just missing that step because it happens in less than 24 hours. I know there wouldn't be nitrite being produced if the plants were handling ALL of the ammonia that's being processed, but there also wouldn't be nitrate present if this were the case, correct? 
 
What I can't determine is - do plants have a preferential source of nitrogen? Meaning, if there is ammonium, nitrite, and nitrate present, will plants go for one first over another? I only took basic biochemistry in college, which was a long time ago, but it makes sense to me that since it takes less energy to reduce nitrite than nitrATE that plants would use nitrite preferentially. So, if there are both bacteria AND plants reducing the nitrite, it would be consumed even more quickly and the plants would move on to using nitrATE once the nitrite was used up. And since there are no bacteria present that are consuming/converting nitrate into anything, it would also be slow to disappear from tests because the plants are using it either second to last or last. 
 
I'm itching to do a near-complete water change and start with a fresh dose of ammonia just to watch the mechanism happen, but impatience is a chronic problem so I should probably just wait it out and see if the ammonia is gone tomorrow night. For some reason, I just want to prove the existence of that nitrite before it gets used up. 
 
I guess none of this will help me cycle the tank, but I'm trying to understand all of the chemistry involved. 

 

[EllieJellyEllie]

From what TwoTankAmin has told me, plants use ammonia and dont convert it into nitrite. The plants may be using all the ammonia, and then also eating up nitrates.

 

[TwoTankAmin]

Plants take up ammonia (well actually ammonium/NH4) and nitrate they do not use nitrite. Different plants do things somewhat differently. But the only time there is a decent level of ammonia available in a tank is during cycling. Once a tank is established, ammonia is pretty much consumed as rapidly as it is created. Moreover in a well planted tank there will be more ammonia in the substrate than in the water, have a read here. Pay attention to what plantbrain writes and ignore the rest of it for the most part.
http/www.plantedtank.net/forums/showthread.php?t=32733

 

[eduller]

I thought there was a whole deal with the Walstad method surrounding the fact that plants prefer nitrite to nitrate as a source of nitrogen? Did I make that up?