[Oslo]

Manure should be well-composted before it is sold to people as an ingredient in potting soil. Doesn't matter whether the manure is originally from chickens, cows, or what-not.
If the soil is growing plants, I wouldn't worry about the smell. Maybe it is a stray worm that's decomposing at the bottom? And whatever it is, the smell probably will decrease as it eventually decomposes. I certainly wouldn't tear down a tank because of it. Just increase aeration and do a water change.
If it truly is manure, you should be able to confirm its presence by measuring ammonia.

You do know that nitrogen is a major plant nutrient? Your plants in Tank #3 may be nitrogen deficient, since the substrate has none and you haven't added fish/fishfood. Same goes for phosphate.

Thank you for constructive feedback. I have added both NH3 and KH2PO4 to the tank regularly in the water layer, but I think I will tear it down and make a dirt tank of it. Here is tank 3:

And here are some close ups:

So, I started to "wash" the forest soil yesterday that I collected this weekend.

and after some "wash" ...........

It contains a very "reddish" color and it is almost only gravel in different sizes left . I have probably washed it too much.I do not think this "soil" contains much nutrition, but if I mix it with one of the commercial garden soils I should be fine perhaps?

Another question, while watching my other tanks yesterday evening, I saw release of bubbles from the bottom layer of the tank with tiger soil, without me poking in it. It seems like this tank have started to release bubbles by itself randomly. I did smell and there was no smell at all at the surface of the tank. Can it be the magic CO2 release from the soil, or is that too early and too naive to expect? And when should I expect the plants to start growing like crazy? I am into week 4 now, is there a particular time point when we should expect great plant grown (if the soil is what we hope it should be for a planted tank)? Is it after 4 weeks, after 8 weeks, or longer?

What I am trying to figure out is which soil I am going to put in tank 3. The soil which release a lot of bubbles or the tank with a faint smell of manure and less bubbles. The tiger soil vs the sowing soil. Ideally, I should just wait and see how the plant growth goes in these two tanks.

Sowing soil
Size: 0-15mm
Organic content: >40%
Density: 440 kg/m³
pH-value: pH 5,5 - 6,5
Totalnitrogen (EN 13654-1 1500 mg/l)

Composition: light peat moss (H2-H4), dark peat moss (H6-H8), sand, organic chicken manure, limestone, kalimagnesia.

Aditions pr. m3:
Magnesium and limestone: 5,5 kg
Chicken manure: 2 kg
Kalimagnesia/patenkail (potassium sulfate and magnesium sulfate): 0,3 kg


"Tiger soil"
Composition: Garden compost, Vermicompost, sand, chicken manure
For outdoor use, can contain worms, for plants in pots, to improve current soil, use nitrogen fertilizer after own choice.
Size: 0 - 10 mm
Density: 580 kg/m3
pH 7,6

Nutrition in mg/L
Nitrogen (N) 3000
Natrium (Na) 46
Ammonium (NH4) 0,23
Sulfat (SO4)10
Nitrat (NO3) 13
Bor (B) 1,2
Fosfor (P) 4,2
Kobber (Cu) 1,7
Kalium (K) 1200
Jern (Fe) 87
Kalsium (Ca) 5300
Mangan (Mn) 3,7
Magnesium (Mg) 160
Sink (Zn) 15

 

[Oslo]

The Forrest soil looks pretty low on organic content. You wash away the clay content it seems. It looks really natural though.

Yeah, I am afraid so, it is a very poor type of forest soil where I live, not much soil, mostly gravel and sand after the ice age. The "uncomposed" peat, grass, pines etc. have more or less been washed out. That`s also why I thought it might be a good idea to mix it with some richer garden soil?

Today, I have ordered a new type of soil from the store, called Ø-kompost (ecological composted plant material and nothing else). If I mix this with some fine sand or the forest "soil" that I have collected it might work out? Would also like to add a tiny spoon of bone meal to the mix for some extra N and P.

 

[Oslo]

Soil/plant question: my Ceratopteris thalictroides turns black, or at least the stem turns black (see pic below). Never seen this with plants before. Ceratopteris thalictroides is the only plant I have that turns black. This seem to occur only in the tank with the "tiger soil". Any comment on that? Ceratopteris thalictroides should be a rapid growing plant with low CO2 demands and moderate need for light exposure.

 

[Oslo]

Question after 4 weeks with the Walstad tanks:

Both tanks with soil (sowing or tiger) contain air bubbles in the soil. After poking with a thin stick it smells really bad from the tank containing sowing soil. Clearly, anaerobic conditions, smelling hydrogen sulfide. What should I do with this tank? The plants seem to do just fine at the moment, growing. The other tank (tiger soil) contain more air bobbles in the soil, but they do not smell (at the moment). Some plants grow in both tanks, at least plants like: Hygrophila polysperma, Nymphaea zenkeri, Nymphoides hydrophylla and Pistia stratiotes. I will add some photos on Monday when I am back after the weekend.

The water test for both tanks:
NH4 = <0,05
NO2 = 0,05
NO3 = 3 (sowing soil) and 5-15 (15 after poking, 5 before poking, tiger soil)

 

[Oslo]

The bubbles with no smell is CO2. You want to leave that alone for the plant.
The anaerobic tank, you want to poke everyday to introduce O2 into the soil. Hopefully the condition goes away over time.

Great! I will poke like a maniac then and hope it will improve over time. Its a bit boring to start all over again if I can avoid it.

 

[Oslo]

Some pictures of the tanks

"Tiger tank"

"Sowing soil"

Question: should/can I remove the 5W powerhead from the lower water layers or should I let it be?

 

[Oslo]

My Pistia (water lettuce) is becoming increasingly pale for every week. Any suggestions for what the reason for this could be?

 

[Oslo]

Makes sense Diana, I bought a JBL iron test kit, and tested for iron yesterday, and there was no iron in the water layer. I will try to add some iron and see if that helps. I have some iron(II)sulphate heptahydrate (FeSO₄·7H₂O) available, may I use it in my tank?

Another question, my pH is quite high, typically 8,0-8,2, should I try to lower it or is it ok? I have just added some snails and guppies now and started up with daily feeding so maybe the pH will drop a bit after a while by itself. (KH=6, GH=8)

 

[Oslo]

Have not seen a "plant response" yet with FeSo4, but my other plants look ok (see pictures).

I will buy another form of iron and see if that can help the floaters.

I am also thinking about finding the optimal gravel size as a cap for the soil. For the two cubic tanks (31L) I used 1-2 mm inert gravel, but for my 54L (60x30x30), I have used 3-5mm inert gravel as a cap (see picture). Can anaerobic pockets be reduced/minimized by using a larger gravel size, or is it only the amount of organic material that decides? I will try to find out...

 

[Oslo]

I am not saying that I will tear the tanks down. I am just asking what the optimal gravel size is as a cap. By optimal, I mean the gravel size that leads to the lowest production of anaerobic pockets in the bottom layer/soil. Will the number of anaerobic pockets be different if I swoop 1-2mm gravel with e.g. 5-8mm gravel? Or is it only the content of the soil that decides production of anaerobic pockets? Anaerobic decomposition do not require oxygen, but uses nitrogen and phosphorus. If I then have a soil with minimal N, P and S (e.g. bark fines), what will then drive the decomposition? Anaerobic bacteria at a very low level I guess (?), and since the soil is low for N, P, S the production of biogas products like methane CH4 and carbon dioxide (CO2) will be very slow or? My four different test tanks (with different soils) have now been filled with one inch 1-2mm cap and water for about 10-11 weeks, three of them produce air bubbles, while the one composed of peat moss and bark fines do not. The three soils ("tiger", "oslo" and "sowing" soil, described in detail earlier in this post) that produce air bubbles are all rich for "nutritions", with added manure.

 

[Oslo]

Gravel size - by itself - has very little to do with creating anaerobic conditions. Anerobic pockets in fish tanks are usually the result of the soil being compacted or weighed down by perhaps too much gravel. A rock, or maybe just the way the soil was packaged before use are other likely contributors. I believe @dwalstad has suggested a relationship between gravel size and healthy root growth in plants.

So, no point in using gravel with larger size then..... Oxygen will flow equally free through 1-2mm gravel as with 5-8mm gravel. The amount of anaerobic pockets are then mainly dependent upon the composition of the soil and off cause the thickness of the gravel layer. So, finding the right balance is then important, you want to keep the soil at the bottom and not in the water layer, but at the same time you want to have as much oxygen in the soil as possible.

 

[Oslo]

I haven't gone back and read through this thread to see what inhabitants you have in your tank, but if shrimp and MTS are part of the equation then I'd go with the 1-2mm size gravel. Much easier for the MTS to burrow in and the shrimp will have an easier time picking up smaller pieces of gravel as they go about their shrimp business. As JohnWesley has pointed out, rooted plants will help prevent anerobic soil conditions, as will MTS. I'm pretty sure Diana refers many times to the role plant roots play in oxygenating the soil. Regarding the depth of the cap, whatever size gravel you decide on, 1 inch is the maximum recommended. You could use less if you want...its main role is to keep the soil from getting into the water column.

I have guppies and nerite zebra snails right now, but I will try to add some shrimps too, So, yes, I will keep at least one tank with gravel size of 1-2mm, even though I probably will get a lot of anaerobic pockets after a while. I have already teared the tank down once. I removed 75% of the soil and re-mixed the soil that was left with 50% 1-2mm gravel before I put a 2cm cap on (with 1-2mm gravel). So the bottom layer is now about 3-4 cm deep with 1-1,5cm soil and 2-2,5cm cap. Lack of solid roots systems in the bottom layer will probably ruin the tank after a while. So, it is best to enjoy the tank as much as possible before everything starts to smell again

Have a great weekend!

 

[Oslo]

This looks like a classic symptom of iron deficiency--yellowing of the youngest leaves. Iron is the one nutrient that can hold back floating plants that depend on water iron. (Rooted plants can get iron from the soil.) Iron is the one nutrient that is often deficient in the water, because it forms iron oxides and precipitates out making it unavailable to plants and algae.

I purchased FeEDTA powder. I quickly make a fresh stock solution of a pinch (200 mg?) in a cup of water and then add this cup to every 10 gallons of tank water. Doesn't have to be exact. I might add it just once or twice a month.

Looks like you was right, after I added some "fresh" iron to the tank my floating plants seem to produce fresh green leaves again.

 

[Oslo]

Plant roots can can keep a soil substrate healthy and not smelly. Unplanted areas should not have a soil underlayer.
In this picture of my tank setup notice how I constructed a front section rimmed with rocks and containing a thin layer of sand with no soil underneath. View attachment 76393

What a great looking tank! What is the name of your red plant in the background? The plant in the upper right comer, is that "guppy grass"?

 

[Oslo]

Nice response. Did you use your FeSO4? Or chelated iron?
Red plant is Rotala macrandra, a gorgeous plant.
I believe that the needle-leaved plant is Star Grass (Heteranthera zosterifolia). It does look like guppy grass.

I did try with FeSO4, but it did not seem to work very well. I therefore bought a product called "flourish iron" from Seachem and now it looks like the floaters are happy again. Yes, the red plant you have is beautiful, I will try to see if it is available here in Norway.

 

[Oslo]

Last update. my floaters grow slowly, but have a nice green color after Fe supplement. In contrast, my H.polysperma grow like crazy (see pictures).Can the reason for the slow growth of the floaters be explained by lack of ammonium in the tank? Water contain enriched levels of nitrate and no ammonium or nitrite.

 

[Oslo]

So, back to the gravel size. In my current tanks I am using gravel size of 1-2 mm resulting in a lot of debris on top of the gravel cap layer (food, fish poo, plant debris etc). Should I do regular vacuum gravel cleaning or should I just let it be? It is not that easy to vacuum clean the gravel in a jungle planted tank......

I currently looking at different gravel sizes as a cap for a garden soil in small tanks. Gravel sizes 1) 1-2 mm 2) 2-4 mm and 3) 4-9 mm.

Do you think I will be able to measure any discrepancy in water parameters between the "tanks" after some weeks/months?

 

[Oslo]

Thanks for your reply, I will leave the debris alone then. It does not look so great with debris at the bottom, but it is not easy to remove the debris either without seriously disturbing the plants. Yes, I am not sure what is going on either, as mentioned the H.polysperma and N. hydrophylla "Taiwan" grows fast, while the floaters, which grew really fast in the beginning are now growing slowly. Another plant that grows slowly is the Red Tiger Lotus (Nypmhaea Zenkeri), and the red Alternanthera Reineckii seem to slowly die (not grow at all). Further, Hygrophila corymbosa is not growing much either, but it is still there, so it is not dying either.
Would have been nice to be able to measure CO2 levels, but I guess you need expensive tools to do that. I think maybe the floaters grow faster with excess of ammonium and nitrite than nitrate? Do not know if iron affects the growth rates of the floaters or the H.polysperma. Maybe it was fish and fish food that increased the growth of H.polysperma.

Anyone had nerite snails in a tank? They seem to lay white eggs on the tank walls and some kind of white slime/mucus that does not look so good. I will try to take a photo of it.

 

[Oslo]

What kind of shrimps would go together with guppies in a low tech dirt tank?

 

[Oslo]

So, after about 2 weeks after setup we can observe two things by looking at the pictures.

1, Different levels of tannins (organic materials) in the water layer.
2. A water surface membrane can be observed in the bottle that contain the highest amount of tannins