Chemistry Help

[remdog]

Hi Everyone...

I have returned to aquariums after a 30 year hiatus, and can use a little advice as I proceed with my 10G tank cycle. Today is the 8th day since I started to cycle the tank, and I am very surprised to see that the NH3 level has dropped from 4.0ppm yesterday, to practically 0 today. NO2 is around 5.0ppm. How far should I bring the NH3 level back up to continue with the process?

Cheers...

Rem

 

[Aqua Tom]

Hi Everyone...

I have returned to aquariums after a 30 year hiatus, and can use a little advice as I proceed with my 10G tank cycle. Today is the 8th day since I started to cycle the tank, and I am very surprised to see that the NH3 level has dropped from 4.0ppm yesterday, to practically 0 today. NO2 is around 5.0ppm. How far should I bring the NH3 level back up to continue with the process?

Cheers...

Rem

Use the calculator to figure this out. Sounds like you may have gone onto second stage cycling so you need to test the Nitrite level now. If they are sky high you need to add 2ppm ammonia from now on. i am sure waterdrop will be along soon to correct me

 

[remdog]

Thanks for the reply, Tom. I have kept track of how much ammonia to add to bring up the NH3 level, and have just added 30 drops to bring the level back up to around 2.0ppm. As I indicated earlier, the nitrites are around 5.0ppm. What surprised me was the sudden drop in NH3 from somewhere around 4.0ppm to nada. BTW, the 10G tank is planted, and I am using an API test kit.

Cheers...

Rem

 

[Aqua Tom]

Your Nitites are through the roof, thats good news. It may be a good idea to start a fishless cycle log like mine . That way the experts on here can see what is going on with your tank & offer advice when needed.

 

[remdog]

Your Nitites are through the roof, thats good news. It may be a good idea to start a fishless cycle log like mine . That way the experts on here can see what is going on with your tank & offer advice when needed.

Yep, NO2 is somewhere at or above 5.0ppm. I am currently testing and dosing on a 24hr schedule. My feeling is that I should dose the NH3 level to around 4.0ppm on a daily bases and closely watch how No2 is behaving. If I understand the process correctly, when NH3 and NO2 have both dropped to 0 within the testing period it's a done deal.

Cheers...

Rem

 

[remdog]

After 24 hrs, this morning's test showed NH3 back to 0, and nitrites off the chart (API test). I guess that confirms that 4.0ppm of NH3 is what the bacteria is able to consume. I added enough NH3 to bring the level back up to 4.0. At this point it is only day 9 in the process, and I am wondering when it would be advisable to start testing for NO3.

Cheers...

Rem

 

[Uriel]

I'm pretty sure during stage 2 your safe only adding 2ppm ammonia rather than 4-5ppm. I think the reason behind this is that the nitrate is acidic and if there is to much of it you can stall the process by making the water too acidic. Hope this makes sense. Plus the nitrite processing bacteria takes a lot longer to grow than the ammonia processing bacteria 2 times as long approximately. So i think dosing 2ppm and testing the nitrite daily is the way to go. The nitrite will drop overnight from off the chart too 0 and at this point you want to up it to 5ppm. Once it can process 5ppm to 0 ammonia and 0 nitrite in 12 hours for 7 days your done.

 

[Mikaila31]

I don't think nitrate NO3 is acidic... if anything I think it would be a base, since it generally carries a negative charge. Anyway its pretty stable so I doubt it would be doing much. I think all the cycle elements are bases: NH3, NO2, NO3. Well actually ammonia has acid and base properties if I remember correctly. Even though they have acid or base properties they are not going to cause much of an effect unless you have water with a low buffering capacity. The only way I know to stall a cycle is to add too much ammonia(above 5ppm).

I'm not familiar enough with the fishless method to say how much NH3 you should be adding. Be aware though that the plants will be consuming some of the ammonia you are adding. Since you do have NO2 your cycle is proceeding normally.

 

[waterdrop]

That's correct Mikaila, its not the NO3 itself that is acidic, its that it dissociates in water and a very small portion of it is in the nitric acid state. Since nitric acid is a very strong acid, it ends up dropping the pH over time if the KH is low enough and the buffering becomes exhausted. This is why we strive to do things that lessen the overall nitrate during the second stage of fishless cycling. By dropping back to perhaps 2 or 3ppm, we can maintain the A-Bacs while ensuring that this small nitric acid component doesn't build up quite as fast.

There is also a completely separate consideration that high nitrite and nitrate levels can slow the N-Bac growth rate just a bit, leaving us with yet another benefit from going slow on our overall levels of nitrogen products.

~~waterdrop~~

 

[remdog]

Very good. Tomorrow morning I shall test all levels again, and if NH3 is back to 0, as it was today, I'll bring up the level to 2ppm instead of 4ppm. I suppose that I should start testing for NO3, and I'm also wondering if the presence of plants in the tank will have a salutary effect.

Cheers...

Rem

 

[remdog]

This mornings readings:

NH3 = 0PPM
NH2 = >5PPM
NH3 = 5ppm

I brought NH3 back up to around 3ppm. NH3 and NH2 seem to be doing just what they are supposed to do at this stage in the game, but I'm not quite sure how to interpret the NH3 level.

Cheers...

Rem

 

[remdog]

The tank seems to be cycling normally, HOWEVER, I am a bit concerned about the PH.

NH3 = 0
NH2 = >5
NH3 = 5
PH = 8.3

The 8.3 figure for PH is as close as I can guess using the API master kit. At any rate PH is definitely well over 8.0 Is that a problem? I am now at day 11 since starting the process.

Cheers...

Rem

 

[Uriel]

Ammonia and nitrite bacteria should do fine in 8.3 ph water. i think between about 7.2 and 8.4 was ideal growing condition for them.

My PH on my fishless was
7.4 Tap water
8.4 Tank water with ammonia in it. Adding the ammonia seemed to boost it.
6.0 About 2 weeks in at which point i had to do a partial water change and added some bicarbonate of soda to buffer the water back up too 7.5.

If your really worried test your tap water to check the PH. 8.3 might be your tap water ph.

 

[remdog]

If your really worried test your tap water to check the PH. 8.3 might be your tap water ph.

Thanks for the reply. I did indeed test the PH of fresh de-chlorinated tap water a few days ago, and it was 7.6

Cheers...

Rem

 

[waterdrop]

For our two species of bacteria, you are right within the plateau of perfection, give that you have 8.3 for pH. 8.0 to 8.4 is the plateau. As you go higher or lower than that the growth rates begin to slow and if you go as low as 6.2 the bacterial growth will stall and stop altogether at 6.0, at least for a while. The bacteria are really reacting to rapid changes in pH more than the actual pH and if the pH were to remain at 6.0 for a very long time the bacteria would recover and be able to operate in it at a slow rate. Biofilters in acid tanks do work. But the point here is that when fishless cycling we want to create an ideal "bacterial growing soup" and not a nice aquarium and you are doing just fine with your soup.

~~waterdrop~~