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Stagnant Parameters

1K views 11 replies 5 participants last post by  Tihsho 
#1 ·
I've been holding off adding fish to my MGOPS cube and it's been over a month the tank has been running. The pH has been stable for 3 weeks, the ammonia has been stable for 2 weeks, but the nitrites are still high (between .25 and .5 PPM) I do 50% water changes on it weekly and only see the nitrite drop post water change but get back to where it was by the middle of the week. This is my first attempt at MGOPS in a tank, so I want to be sure prior to adding some fish. MTS, Ramshorns and Scuds are conquering the tank and have made it home. Now I just want to add something to take care of algae such as two baby BNP's to temporarily be housed in there till they need to go. Or yet again try Oto's, though no matter the tank I've never had luck with them.

Thoughts?
 
#3 ·
Are the conditions currently really good for the nitrifying bacteria to grow?
I'd hope so. The sponge that was used to seed the tank came from my Viv that has a decent bioload. I noted and charted the water tests every week (like I do in all my tanks) and the only thing that has not settled is the Nitrites and Nitrates (5.0 ppm.)

Is this tank planted?
Yep. Here is a shot of it as of a few days ago.



Perhaps there is a problem with the test kit, and you really do have a cycled tank.
I use the same test kit across 3 tanks (two full tanks and a viv) and the other setups are spot on perfect, so doubting the kit is a little hard.

I do have some chemical 'neutralizers' I could use, but I don't want to go that route as I only like to use them when acclimating fish.
 
#4 ·
I think there is something going on here that is slowing the growth of the Nitrospira species of bacteria. These are the ones that are more sensitive to the parameters, and are slow growing. These are the ones that turn NO2 into NO3.

Here is the fishless cycle. Look through it for the optimum parameters for growing these bacteria as fast as possible. See if your tank meets these requirements and keep on feeding the bacteria with ammonia.

Fishless Cycle

Set up tank and equipment.
Fill with water, including dechlor.
Optimum conditions to grow these bacteria the fastest:
GH and KH at least 3 German degrees of hardness, and higher is just fine.
Add some other minerals, for example plant fertilizers: KH2PO4, trace minerals.
High oxygen levels.
Good water movement.
A place to grow. They grow on surfaces, not drifting free in the water. Filter media is great. Sponges, floss, bio-media are all good places for these bacteria.
You can add a starter culture of the right bacteria if you want. It is optional. The cycle can go faster if you add something. Media from a cycled, healthy filter. Bottled bacteria containing Nitrospira species of bacteria. Do not waste money on anything else.

Add ammonia (no surfactants, no perfumes) to test 5 ppm.
Test daily. Add more ammonia to keep the test at 5 ppm through the first few days.
Test for nitrite. When nitrite shows up allow the ammonia to drop to 3 ppm.
Test daily, adding enough ammonia to bring the test to 3 ppm once a day. If you are growing plants that do not like this level of ammonia then test twice a day, and add enough ammonia to bring the test to 1 ppm twice a day.
If the nitrite gets to 5 ppm do a water change. Perhaps add less ammonia for a few days. The nitrite removing bacteria (Nitrospira species) are slower growing, and the ammonia removing bacteria might be making more nitrite than they can deal with.

When the ammonia returns to 0 ppm after 24 hours, and no nitrite shows up at that same 24 hour mark, then the cycle is done.
A fishless cycle with no plants might have VERY high nitrate. Do a BIG water change, or even a couple of them to get the nitrate way down before adding the fish. You can fully stock the tank.
A fishless cycle with lots of plants might show almost no nitrate. The plants are part of the bio filter, and are removing a certain amount of the ammonia before the bacteria even have a chance to turn it into nitrate, and then the plants are removing some or all of the nitrate produced by the bacteria. I would still do a big water change.

If the fish you want to keep need water different than the hard, alkaline water that grow the bacteria so well, now is the time to change that to softer, acidic water. While you were trying to grow the bacteria as fast as possible you wanted optimum conditions for the bacteria. Now that the colony is well established you can change the conditions. They might not grow so fast, but that is OK.
 
#5 ·
Hrm, I wasn't trying to go through a chemical cycle. I'll put that on the todo list if things don't improve. I'm surprised as my other tank of the same size cycled perfectly, within a few weeks, using the method I've been using for years.

My concern is that the organics from the MGOPS is throwing off the tests. As I've gone from 4.0 ppm of ammonia to 0 ppm I'm stuck thinking either the cycle kinda finished or it crapped out. The fact that the Nitrites are not converting to ammonia is the issue I guess I'm trying to get at.
 
#8 ·
I'm actually feeding the tank daily since the MTS tear up anything that hits a pyrex dish that I put in at feeding time. As for other sources of ammonia, no. That logically sounds like the issue.

The ammonia converts to nitrites which are converted to nitrates.
The fishless cycle only attempts to maximize the presence of the ammonia in
order to keep the process going throughout the entire cycle for it to complete.
The way you do it works of course. The "fishless' is just an ammonia source being
provided that does not have fish as it's source so as not to hurt them.
If you had but now don't have any ammonia reading, it may be that the cycle was cut short by running out of ammonia. When you put the plants in there the Beneficial Bacteria were introduced on them. A slow way to go but works non the less.
But these bacteria only live so long without more ammonia. This usually comes from putting in the fish once nitrates are established.
Dammit, I was looking at the process backwards. That's where my confusion lies. Bear with me, it's been a few years since I decided to start back up a month ago. The plants I can see, through the general process, are assisting in being nutrient sponges. In the case of Amm, Nitrite, and Nitrate those organics are just acting as a large nutrients for the plants. I'll hop on some ammonia tomorrow to get this cycle done. I'm only anxious as I'm getting tired of the GSA and now as of recent some diatoms growing on my S. Repens.
 
#7 ·
The ammonia converts to nitrites which are converted to nitrates.
The fishless cycle only attempts to maximize the presence of the ammonia in
order to keep the process going throughout the entire cycle for it to complete.
The way you do it works of course. The "fishless' is just an ammonia source being
provided that does not have fish as it's source so as not to hurt them.
If you had but now don't have any ammonia reading, it may be that the cycle was cut short by running out of ammonia. When you put the plants in there the Beneficial Bacteria were introduced on them. A slow way to go but works non the less.
But these bacteria only live so long without more ammonia. This usually comes from putting in the fish once nitrates are established.
 
#9 ·
If it foams when shaken or has color in it don't. All ammonia is cut/w water but no
other chemicals should you allow...perfume etc.
Some people say hrs some say days for the BB to die without ammonia.
If you add ammonia to 1 ppm and after 24 hrs you still have that 1 ppm the BB may have died. You would need to "seed" it in this case. But if it drops in that 24 hrs you
can add more to bring it up to the 5 ppm or anything under that. The 5 ppm is optimim
but also for optimum production of many/a high level of those bacteria.
So that 5 ppm is used so that you can add all your fish immediatelty after your cycle is done as there will be suffient bacteria. So the 5ppm is an optimum not a requirement.
 
#11 ·
Would just add some more seed material from other tank's and reduce food for bacteria to every other day assuming you are using fish food as ammonia.
Adding liquid ammonia at this point could stimulate algae that in my experiences thus far loves light + ammonia.
Is why they suggest large water change after rescaping to neutralize ammonia that may occur due to organic's in substrate being disturbed = possible algae.
 
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