[Oslo]

Soil consisting of 60% peat moss, 40% composed bark fines and iron sulfate (50g/m3) additive, would it be ok for a Walstad tank even if it has a pH of 4? Or would it be beneficial to have a soil exclusively consisting of either peat moss or compressed bark fines?

Cheers,

 

[johnwesley0]

I think you're erring way too far on the side of caution. Peat moss has 0% nutrients and I'm not sure what "bark fines" are. To me, it sounds like a fancy word for "saw dust". Aquatic plants don't uptake nutrients quite as fast as terrestrial plants - but they still need their share of nitrogen by-products derived from slowly decomposing organic matter. The trick is finding that happy medium where the plants are being fed without poisoning the livestock that makes its home in the same ecosystem. Commercially available potting soils that grow houseplants can be "mineralized" (rinsed and flushed) in order to step down their toxicity under water. My current favorite is Miracle-Gro's "Cactus, Palm and Citrus Potting Mix" , but I'm sure there are others.

 

[Michael]

Since that soil is 100% organic matter, I suggest that you soak and drain it several times. Then mix it half and half with a high CEC inorganic substrate. I don't know what is available in your location, but here we often use some type of fired clay product.

The soak and drain procedure will rinse most of the tannins out of the peat and pine bark that would otherwise cause tea-colored water. Tannins are not harmful per se, but may be aesthetically undesirable. Peat and pine bark are not high in nutrients, so that should not be a problem.

 

[Oslo]

Since that soil is 100% organic matter, I suggest that you soak and drain it several times. Then mix it half and half with a high CEC inorganic substrate. I don't know what is available in your location, but here we often use some type of fired clay product.

Thanks for the advise, you mean unfired red clay right? Will this french red clay do the magic?

 

[FernKing]

Soil consisting of 60% peat moss, 40% composed bark fines and iron sulfate (50g/m3) additive, would it be ok for a Walstad tank even if it has a pH of 4? Or would it be beneficial to have a soil exclusively consisting of either peat moss or compressed bark fines?

Cheers,

Diana has experimented with a wide variety of potting soils so far with success but peat moss seems to be the universal “no”. I would look for a different soil. Use that bag for house plants.

 

[Oslo]

Diana has experimented with a wide variety of potting soils so far with success but peat moss seems to be the universal “no”. I would look for a different soil. Use that bag for house plants.

Strange, I believe Miracle-Gro Organic Choice potting mix consist of a blend of sphagnum peat moss, composted bark fines and natural fertilizer. That`s why I tried to find something similar here in Norway.

 

[johnwesley0]

Strange, I believe Miracle-Gro Organic Choice potting mix consist of a blend of sphagnum peat moss, composted bark fines and natural fertilizer. That`s why I tried to find something similar here in Norway.

I understand what you are trying to do. However, I just took a look at the ingredients of my store-bought Miracle-Gro and it doesn't go into much detail in terms of how much of either ingredient they use. I suspect in both cases they are being used as additives.

 

[FernKing]

Strange, I believe Miracle-Gro Organic Choice potting mix consist of a blend of sphagnum peat moss, composted bark fines and natural fertilizer. That`s why I tried to find something similar here in Norway.

You can buy pure peat moss and 60% peat is a very high amount. I would avoid it.

 

[mistergreen]

Soil high in organic matter will always go anaerobic. You can help by sifting out big bits of organics and adding in sand to reduce the organics.

 

[johnwesley0]

I understand what you are trying to do. However, I just took a look at the ingredients of my store-bought Miracle-Gro and it doesn't go into much detail in terms of how much of either ingredient they use. I suspect in both cases they are being used as additives.

I'd like to amend what I stated upstream in answer to the thread starter's question. I did a quick google search of the question, "How much peat moss is in Miracle-Gro potting mix?" Potting mix is a term of art used within the industry to differentiate between it and garden soil. Potting mixes are intentionally filled with peat moss roughly in the proportions you propose to use (anywhere from 50-80%) so that the water does not drain so fast that the houseplant roots have no chance to absorb the moisture. One important consequence of using so much peat moss in commercial potting mixes is that they have to compensate for the lack of nutrients in peat by adding "slow-released" nutrients to the product. Apparently, this has worked out well for hobbyists over the years (Walstad, "Ecology of the Planted Aquarium", page 137)

So, if you are going the DIY route, you will probably wind up having to add ferts. Another suggestion might be to add organic garden soil to what you have.

 

[dwalstad]

Strange, I believe Miracle-Gro Organic Choice potting mix consist of a blend of sphagnum peat moss, composted bark fines and natural fertilizer. That`s why I tried to find something similar here in Norway.

I would not try to second-guess soils and ingredients. Just get an ordinary, inexpensive potting mix that people in Norway use to grow houseplants. I'm going to assume that any commercial potting soil will contain enough nutrients to get started. Later on, if you see nutrient deficiencies, you can consider fertilizers.

 

[Oslo]

Peat moss have a carbon:nitrogen ratio of 58:1 and bark 100-130:1

autumn leaves	30-80:1
straw	40-100:1
wood chips or sawdust	100-500:1
bark	100-130:1
mixed paper	150-200:1
newspaper or corrugated cardboard	560:1

MGOCPM, highly recommended by Walstad as soil in a dirted tank has peat moss and composed bark, same as the soil I found here in Norway (see picture below). If I understand correct, peat moss, composed bark and wood pellets consist primarily of cellulose and lignin, and are mostly carbon.

The question is how much nitrogen do you want in your soil?

Quoted from Aquarium Science – The Science of Aquariums : "Most (but not all) rooted “vascular” plants have been shown by testing to absorb phosphorus and iron from their roots much better than from their leaves. Most (but not all) vascular rooted plants also absorb potassium and nitrogen much better through their leaves".

So, if we would like to follow this "guideline" it would be vice to have a soil rich in carbon, iron, and phosphate, while the water layer should contain potassium and nitrogen, true or false?

An organic carbon-rich soil mixed with bonemeal or fish meal to add phosphate combined with iron sulfate would do it or?

In addition, I would like to mix the soil with aragonite sand to increase the KH/pH and make it more friendly for guppies. This sand also works like a natural filter to remove nitrogenous waste (see link: Nature's Ocean Bio-Activ Live Aragonite Sand 9kg - )

CO2 production dependent upon pH, see link: https://bg.copernicus.org/preprints/6/491/2009/bgd-6-491-2009.pdf

MGOCPM soil:

View attachment 75802

The Norwegian rhododendron soil with peat moss, composed bark, and iron, nothing more, nothing less. pH=4

 

[johnwesley0]

Your missing ingredient is the "slowly available nitrogen" that is included in packaged potting mixes. It is a euphemism for animal (in the above case, poultry) manure. Good luck experimenting with that.

 

[Oslo]

Your missing ingredient is the "slowly available nitrogen" that is included in packaged potting mixes. It is a euphemism for animal (in the above case, poultry) manure. Good luck experimenting with that.

Thank you I like a challenge!

Do you think aragonite sand mixed with lava stones would be sufficient as an ammonia removal system in a low tech tank without plants?

 

[mistergreen]

No need to add bone meal and fish meal in the soil. It’s a recipe for disaster. The smell is awful too.
You can add a little bit of limestone or coral to add calcium and balance the pH in the soil.

plants are an important ingredient in a dirt tank. You need plants.

 

[dwalstad]

#1 The question is how much nitrogen do you want in your soil?

Quoted from Aquarium Science – The Science of Aquariums : "Most (but not all) rooted “vascular” plants have been shown by testing to absorb phosphorus and iron from their roots much better than from their leaves. Most (but not all) vascular rooted plants also absorb potassium and nitrogen much better through their leaves".

#2 So, if we would like to follow this "guideline" it would be vice to have a soil rich in carbon, iron, and phosphate, while the water layer should contain potassium and nitrogen, true or false?

#3 An organic carbon-rich soil mixed with bonemeal or fish meal to add phosphate combined with iron sulfate would do it or?

#1 Not too important. Commercial soils designed for houseplants should have enough N. Let fish waste (via fishfood) provide the water ammonia plants like.

#2 Yes. You definitely want soil to contain phosphates and micronutrients. Some carbon is okay to provide CO2 via decomposition, but too much and soil easily goes anaerobic. Ideally, I would use a forest or agricultural soil with 5-10% organic matter, but most people don't have access to good mineral soils. I would try to work with potting soils with their less than ideal 60-80% organic matter. Mix them 50:50 with STS or sand. Or mineralize them via Michael's procedure to decrease the decomposition. As my book shows (Fig VIII-5, p. 130), even acidic soils become neutral over time following submergence (e.g., one soil with a starting pH of 4.5 was ~6.2 pH within 3 weeks).

#3 I think a little bone meal mixed with the soil is good and I use it. It contains not only Ca/Mg and carbonates but P, which is really important to have in the soil. I would not add iron sulfate to a potting soil. Both iron and sulfates in potting soils can cause problems. A decent potting soil should contain enough Fe.

 

[Oslo]

Great, thank you! Your comments helped a lot. There are a lot of different garden soils available, I will look for one without peat and bark then.

 

[dwalstad]

I would use small amounts of bone meal.

Potting soil containing peat is fine; it is processed and fertilized. You have to trust the manufacturer to sell a product--whatever manure, bird dropping, compost it contains-- that will grow plants. Otherwise, the company would not stay in business.

Pure 'peat moss' sold in bags labeled peat moss, I would never use. Too acidic, no iron, no P, etc.

 

[Oslo]

I have found some products with information about the soil. Could I use one of these?

A. Pottering soil:
Size: 0-35 mm
pH-value: 6,0
Organic content: >60%
Density 450 kg/m3
Total nitrogen (EN 13654-1) 2400 mg/l

Composition: light peat moss (H2-4), dark peat moss (H6-8), sand, limestone, fertilizers

Additions pr. m3:
Limestone: 3,5 kg
Dolomitt: 2 kg
Chicken manure: 5 kg
Fertilizer NPK 12-4-18: 1 kg

Nutrition in g/m3:
Nitrogen(N):310
Bor (B):0,6
Kobber (Cu):0,85
Fosfor (P):95
Jern (Fe):3
Kalium (K):280
Mangan (Mn):4,25
Kalsium (Ca):1950
Molybden (Mo): 0,03
Magnesium (Mg):260
Sink (Zn):2,9
Svovel (S):120

B. 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

Nutrition, mg/l:
Nitrogen(N)/(NO3-N+NH4-N): 80
Bor (B): 0,2
Kobber (Cu): 0,6
Fosfor (P): 25
Jern (Fe): 50
Kalium (K): 150
Mangan (Mn): 7
Kalsium (Ca): 225
Molybden (Mo): 0,1
Magnesium (Mg): 220
Sink (Zn): 2
Svovel (S): 60

C. Plant soil
Size 0-35 mm
pH-value: 6,0
Organic content >80%
Density: 390 kg/m3
Total nitrogen (EN 13654-1) 1500 mg/l

Composition: light peat moss (H2-4), dark peat moss (H6-8), sand, limestone, fertilizer

Additions pr. m3:
Limetone: 3 kg
Dolomit: 2 kg
Fertilizer NPK 11-5-18: 1 kg

Nutrition: mg/l:
Nitrogen(N)/(NO3-N+NH4-N): 110
Bor (B): 0,3
Kobber (Cu): 0,5
Fosfor (P): 45
Jern (Fe): 40
Kalium (K): 210
Mangan (Mn): 19
Kalsium (Ca): 200
Molybden (Mo): 0,2
Magnesium (Mg): 230
Sink (Zn): 3,5
Svovel (S): 150

D. Top soil
Composition: Natural sand, garden compost, and some kind of animal (unknown) manure
For upper lawn layer and sowing of grass, for flowers and plants.
Has huge amounts of "reserve" plant nutrition.
Deposit nutrition over a long time period.
High pH, no need for limestone products.
Recommend to add nitrogen fertilizer dependent upon plant grow wanted
Size: 0 - 10 mm
Density: 955 kg/m3
pH 7,5 - 8,5

Nutrition:
Nitrogen (NH 4 - N + NO 3 - N) 4,8 + 15,01 mg/L
Fosfor (P) 21,7 mg/100 g
Kalium (K) 100 mg/100 g
Magnesium (Mg) 39 mg/100 g
Kalsium (Ca) 378 mg/100 g

E. "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

F. Oslo soil
Composition: Leafs, branches and grass
For plants, flowers, kitchen garden, light structure, high pH, deposit nutrition over a long time, recommend addition of nitrogen fertilizer after needs.
Size: 0 - 10 mm
pH 7,5 – 8,5
C/N: 17,5

Nutrition:
Ammonium (NH4) 8,3
Nitrat (NO3) 56
Bor (B) 1,5
Fosfor (P) 36
Kobber (Cu) 1,7
Kalium (K) 2100
Jern (Fe) 26,3
Kalsium (Ca) 2574
Mangan (Mn) 2,8
Magnesium (Mg) 141
Sink (Zn) 16
Svovel (S) 49

 

[johnwesley0]

The answer is probably "All of the Above", but I'm not gonna lie. I really like D. Top Soil. It's one of the choices that don't mention fertilizer as an ingredient and the sand makes me think it has already been "mineralized" in the traditional sense of the word. You will probably still have to do a fair amount of rinsing and flushing to step down the nitrogen by-products to a non-toxic level, but that is pretty much par for the course.