Substrate question

[TianChen]

Disclaimer : i am not a Dutch tank guy, but i DO grow aquatic plants, just not in the way you guys are doing. I mostly do semi-emersed, and want to know your experience around this.

It is very rare to find mud as a substrate, meanwhile it is the main substrate in nature? I found that with a dirted tank , a mixture of 1:1 mud and sand being beneficial : clay mud has high cec , and it doesnt leak nutrition as much as pure soil with sand cap? Besides, i found that despite the idea of anaerobic, aquatic plants seems to root better in mud?

I know there is a concern of anaerobic but in nature, anaerobic is default and helophytic plants has evolved numerous mechanisms to overcome it. Besides, in Amazon streams and lakes, mud and sediment does not leach nutrient in water column as fast as aquasoil or potting soil.

 

[Kwyet]

No experience with mud, but I would love to see some pictures.

 

[Art]

I will disclaim this by saying I haven’t done any experiments so my response is based solely on my experience and assumptions resulting therefrom.

Yes, some plants have developed the ability to bring oxygen to the root zone and, therefore, create a semi aerobic environment in an otherwise anaerobic or anoxic one. However, this isn’t ideal, especially in an aquarium environment. We are dealing with a very small environment compared to a river.

I believe an aerobic environment is going to be more beneficial for the plant roots and the ecosystem that develops in the substrate. I’ve had anaerobic substrates before and the roots all rotted.

I have two questions- 1. What do you mean by “mud”? And 2. Why do you think this works better than other substrates that maintain an aerobic environment?

Not being argumentative, just trying to understand your perspective.

 

[TianChen]

I will disclaim this by saying I haven’t done any experiments so my response is based solely on my experience and assumptions resulting therefrom.

Yes, some plants have developed the ability to bring oxygen to the root zone and, therefore, create a semi aerobic environment in an otherwise anaerobic or anoxic one. However, this isn’t ideal, especially in an aquarium environment. We are dealing with a very small environment compared to a river.

I believe an aerobic environment is going to be more beneficial for the plant roots and the ecosystem that develops in the substrate. I’ve had anaerobic substrates before and the roots all rotted.

I have two questions- 1. What do you mean by “mud”? And 2. Why do you think this works better than other substrates that maintain an aerobic environment?

Not being argumentative, just trying to understand your perspective.

1. It is a mixture of clay, silt, mulm and small amount of slow decay organic matters.
2. From my personal observation, it reduces the speed of water remineralisation, on top of it can cover and pack a better punch of nutrients. Mud has really good cec , and i grow stuff mostly outside, so it bombards insane amount of light, but water changes i can only do once per week due to job ( and that is 10+ tubs). I have always faced problem with aquasoil under sun, they tend to burst algae from the substrate.

Mud has higher cec which is obvious, but there is another part to it - it decays so slow and tend to inhibit the remineralization - whatever the decay product is trapped in the mud matrix. This happens so frequent in nature - ponds and lakes have mud, obviously, but it never has big algal bloom ( unless getting eutrophicated by runaway) due to how stable the physiochemical properties of mud. Mud also has really fine particles and can support carpeting plant so well, and for some unexplained reason i always find the root system in mud way more robust than whatever i have with aquasoil - i think it is due to the fact that the plants themselves are evolved to grow on the mud.

I do take account of root rotting of anaerobic, but usually it is because a phenomenon called xylem clogging. The plant requires to have some roots before planted, because if you just plug them directly into mud they will clog the xylem of the plants and make it rot away.

 

[ElleDee]

I am very interested in substrate systems and these days am favoring DIY substrates over aquasoil, mainly for cost and aesthetic reasons. I also just think substrates are neat, so I am happy to reinvent the wheel so to speak to satisfy my own curiosity. It didn't seem like you had a specific question, so I'll just add my thoughts to what you've said.

It is very rare to find mud as a substrate, meanwhile it is the main substrate in nature?

Sure, but we aren't really trying to grow things exactly like they grow in nature. We are aiming for an aesthetic and functionality specific to an aquarium, not perfectly replicating a natural ecosystem. Aquatic ecosystems have the soil that they do because they are bound by natural processes that dictate the specific physical and chemical properties, and those are not necessarily ideal for the plants that grow there. The natural world can give us clues to how to grow these plants of course, but it is never the final word in what conditions would be best.

I found that with a dirted tank , a mixture of 1:1 mud and sand being beneficial : clay mud has high cec, and it doesnt leak nutrition as much as pure soil with sand cap?

I'm not clear what your "pure soil" is here. If it's leaching a lot of plant nutrients it may have more nutrients than it's ion exchange capacity, and yeah, those are going to dump into the water column. That should become less pronounced as your tank matures though.

Besides, i found that despite the idea of anaerobic, aquatic plants seems to root better in mud?

I know there is a concern of anaerobic but in nature, anaerobic is default and helophytic plants has evolved numerous mechanisms to overcome it. Besides, in Amazon streams and lakes, mud and sediment does not leach nutrient in water column as fast as aquasoil or potting soil.

I think that the main concern is more hydrogen sufide production than anaerobic conditions generally. (Methane is an issue in natural wetlands, but I've never heard of it in an aquarium. Maybe someone has run into it, idk.) I haven't actually experienced H2S myself, but my working understanding is that if you have a substrate that is rich in organic matter you need to keep your depth to about an inch or less and it will probably be ok. Aquasoil seems to be immune to this though, and you can pile it high without worry. I think this is largely due to the fact its large structure makes huge channels that allows water to flow through it, but I'm not totally sure. I have made my own substrates much deeper than an inch, but I include larger particles for this reason.

Anaerobic soil conditions are the norm in bulk submersed soil, but lots of roots will create a substantial rhizosphere with lots of little microniches that will enhance the availability of certain nutrients, neutralize various toxic compounds, and return oxygen and organic material to the soil.

1. It is a mixture of clay, silt, mulm and small amount of slow decay organic matters.

This is the same stuff that aquasoil is made of, more or less. What are you including for your slowly decaying organic matter?

2. From my personal observation, it reduces the speed of water remineralisation, on top of it can cover and pack a better punch of nutrients. Mud has really good cec, and i grow stuff mostly outside, so it bombards insane amount of light, but water changes i can only do once per week due to job ( and that is 10+ tubs). I have always faced problem with aquasoil under sun, they tend to burst algae from the substrate.

Mud has higher cec which is obvious, but there is another part to it - it decays so slow and tend to inhibit the remineralization - whatever the decay product is trapped in the mud matrix. This happens so frequent in nature - ponds and lakes have mud, obviously, but it never has big algal bloom ( unless getting eutrophicated by runaway) due to how stable the physiochemical properties of mud. Mud also has really fine particles and can support carpeting plant so well, and for some unexplained reason i always find the root system in mud way more robust than whatever i have with aquasoil - i think it is due to the fact that the plants themselves are evolved to grow on the mud.

The algae issue may come down to the high ammonia content of some aquasoils, but also I would not assume that your results in a pond or semi emersed will be the same in an aquarium indoors. Some stuff will translate over, and other stuff may be different than you were expecting. I have a conventional horticulture background, so I'm experiencing this constantly.

I do take account of root rotting of anaerobic, but usually it is because a phenomenon called xylem clogging. The plant requires to have some roots before planted, because if you just plug them directly into mud they will clog the xylem of the plants and make it rot away.

Huh, I had never heard of this before. Interesting!

 

[TianChen]

I am very interested in substrate systems and these days am favoring DIY substrates over aquasoil, mainly for cost and aesthetic reasons. I also just think substrates are neat, so I am happy to reinvent the wheel so to speak to satisfy my own curiosity. It didn't seem like you had a specific question, so I'll just add my thoughts to what you've said.


Sure, but we aren't really trying to grow things exactly like they grow in nature. We are aiming for an aesthetic and functionality specific to an aquarium, not perfectly replicating a natural ecosystem. Aquatic ecosystems have the soil that they do because they are bound by natural processes that dictate the specific physical and chemical properties, and those are not necessarily ideal for the plants that grow there. The natural world can give us clues to how to grow these plants of course, but it is never the final word in what conditions would be best.


I'm not clear what your "pure soil" is here. If it's leaching a lot of plant nutrients it may have more nutrients than it's ion exchange capacity, and yeah, those are going to dump into the water column. That should become less pronounced as your tank matures though.


I think that the main concern is more hydrogen sufide production than anaerobic conditions generally. (Methane is an issue in natural wetlands, but I've never heard of it in an aquarium. Maybe someone has run into it, idk.) I haven't actually experienced H2S myself, but my working understanding is that if you have a substrate that is rich in organic matter you need to keep your depth to about an inch or less and it will probably be ok. Aquasoil seems to be immune to this though, and you can pile it high without worry. I think this is largely due to the fact its large structure makes huge channels that allows water to flow through it, but I'm not totally sure. I have made my own substrates much deeper than an inch, but I include larger particles for this reason.

Anaerobic soil conditions are the norm in bulk submersed soil, but lots of roots will create a substantial rhizosphere with lots of little microniches that will enhance the availability of certain nutrients, neutralize various toxic compounds, and return oxygen and organic material to the soil.


This is the same stuff that aquasoil is made of, more or less. What are you including for your slowly decaying organic matter?

The algae issue may come down to the high ammonia content of some aquasoils, but also I would not assume that your results in a pond or semi emersed will be the same in an aquarium indoors. Some stuff will translate over, and other stuff may be different than you were expecting. I have a conventional horticulture background, so I'm experiencing this constantly.

Huh, I had never heard of this before. Interesting!

oh boy, a lot of stuff to answer here. The two main reasons that i switched to mud is cost ( of course!) and secondly it seems like aquasoil failed me more than i expected.

This is the same stuff that aquasoil is made of, more or less. What are you including for your slowly decaying organic matter?

about this, i don't use mud as a pure substrate, it is wayy too inconvenient using them directly as pure substrate. What i am doing exactly is to use them as substrate cap - it is a bit more complicated than you expect.

Typically i will start with a 5 inch tall pot, 12' in diameter. In the bottom layer i use at least one inch of vermicompost but vermicompost is highly chaotic, so it got to be capped with a layer of dark humus ( almost fully decayed humus) mix with rice/barley husk one inch. The third layer is powdered soil, one inch, the capping layer is where mud is used - i mix it with sand 1:1 in ratio, try to seal whatever the nuclear bomb of nutrient below. The last inch i capped with exhausted aquasoil and gravel so the mud don't float around.

Sure, but we aren't really trying to grow things exactly like they grow in nature. We are aiming for an aesthetic and functionality specific to an aquarium, not perfectly replicating a natural ecosystem. Aquatic ecosystems have the soil that they do because they are bound by natural processes that dictate the specific physical and chemical properties, and those are not necessarily ideal for the plants that grow there. The natural world can give us clues to how to grow these plants of course, but it is never the final word in what conditions would be best.

Now this is contrast to my framework, i think it backwards. It is true that plants don't grow in optimal conditions in nature due to various reasons, however there is a thing : evolution - plant evolve themselves to adapt right into these niche, and the thing is not all of these niche is bad for the plant's 'optimal state' - so there are conditions that inhibits the plants and it tolerates, but for some it more like the plant's physiology adapted to such. And at least from my experience, anaerobic isn't exactly inhibiting it.

I'm not clear what your "pure soil" is here. If it's leaching a lot of plant nutrients it may have more nutrients than it's ion exchange capacity, and yeah, those are going to dump into the water column. That should become less pronounced as your tank matures though.

it means topsoil only. I try a lot of substrate types before i was pushed into mud. Topsoil with direct water topped on it will somehow "foul" -it doesn't leak minerals only, it will also release a significant amount of dissolved organics into the water and unless you can do daily water changes it is mostly not possible using soil without presoaking.

Mud has two properties: firstly its particle sizes - micron in sizes - it can bind so very well to organic detritus and sink them down,. Mud can capture undissolved organics materials ( due to a process called flocculation )-by that it also reduced the general doc in the water - and the anaerobic properties is what makes me choose it - whatever traps in the mud decays so slow it won't foul the water as quickly as topsoil.

I think that the main concern is more hydrogen sufide production than anaerobic conditions generally. (Methane is an issue in natural wetlands, but I've never heard of it in an aquarium. Maybe someone has run into it, idk.) I haven't actually experienced H2S myself, but my working understanding is that if you have a substrate that is rich in organic matter you need to keep your depth to about an inch or less and it will probably be ok. Aquasoil seems to be immune to this though, and you can pile it high without worry. I think this is largely due to the fact its large structure makes huge channels that allows water to flow through it, but I'm not totally sure. I have made my own substrates much deeper than an inch, but I include larger particles for this reason.

I am working on creating a different type of substrate that can vent out hydrogen sulfide, but as the time, the general rule is don't disturb the substrate layer - but we can work around this somehow

The algae issue may come down to the high ammonia content of some aquasoils, but also I would not assume that your results in a pond or semi emersed will be the same in an aquarium indoors. Some stuff will translate over, and other stuff may be different than you were expecting. I have a conventional horticulture background, so I'm experiencing this constantly.

about this i woudn't expect it can translate perfectly as well but i really want to push for an experiment, and it's not like people don't do dirted co2 tanks.

 

[Minorhero]

It seems you are not really doing an aquarium but either just an emersed plant or maybe a pond? (you mentioned tubs?) Is this 12 inch pot something you observe ever from an aquarium?

I think a lot of people are having trouble with your terminology. One thing that's nice about aquasoil is its repeatability. If I go buy a bag of UNS controlsoil, its going to be the exact same product that someone else buys on the other side of the planet when they go buy a bag of UNS controlsoil. etc.

On the other hand when you say things like "humus", "powdered soil" or just "mud", that doesn't really tell us what you are using at all. Humus to me is what is in the top inch or so of my vegetable gardenbed or maybe under the leaves in the forest. If that's what you are referring to then say so, how do you collect it? It will matter if its from your lawn or from vegetable garden or from a forest etc. If its not a product from a store we are not going to be able to recreate it, but at least we will know what you did so we can try to approximate it.

The same goes for mud, to most people mud is what happens when it rains on the dirt. Where are you getting your mud? Are you digging it up from a stream bed? Are you 'creating' it from mixing store bought purified clays? Are you literally taking a shovel to the middle of your lawn? These kinds of details matter because again, repeatability, or the ability to approximate what you are trying to do.

 

[TianChen]

It seems you are not really doing an aquarium but either just an emersed plant or maybe a pond? (you mentioned tubs?) Is this 12 inch pot something you observe ever from an aquarium?

I think a lot of people are having trouble with your terminology. One thing that's nice about aquasoil is its repeatability. If I go buy a bag of UNS controlsoil, its going to be the exact same product that someone else buys on the other side of the planet when they go buy a bag of UNS controlsoil. etc.

On the other hand when you say things like "humus", "powdered soil" or just "mud", that doesn't really tell us what you are using at all. Humus to me is what is in the top inch or so of my vegetable gardenbed or maybe under the leaves in the forest. If that's what you are referring to then say so, how do you collect it? It will matter if its from your lawn or from vegetable garden or from a forest etc. If its not a product from a store we are not going to be able to recreate it, but at least we will know what you did so we can try to approximate it.

The same goes for mud, to most people mud is what happens when it rains on the dirt. Where are you getting your mud? Are you digging it up from a stream bed? Are you 'creating' it from mixing store bought purified clays? Are you literally taking a shovel to the middle of your lawn? These kinds of details matter because again, repeatability, or the ability to approximate what you are trying to do.

oh okay, you really make a good point there actually. My humus is actually leaf composted together with rice husk, which was purchased from local dealer. Leaves were actually grounded to powder and composted, together with straw and coconut husk.

About mud, i stated earlier it was POND mud, in natural pond ( with no surrounded trees for more detail), and it isn't too clay heavy. It is hard to describe its texture tho, usually I use it when it was dried one week, grounded, mixed with sand and rehydrated in to grey sludge, and a very thick sludge.

For powdered soil, it is topsoil left to dry, and then again grounded to about 0.5-1mm grain

 

[TianChen]

a bit of update, I just found a way to prevent the xylem clogging and venting hydrogen sulfide : simply by layering the bottom of container with sand + inert aquasoil , then poke a hole and pour the sand + aquasoil mixture into it. The hole is like 1-2 mm, can be done by simply using a drinking straw.

Plant will be planted into this column of sand mixture - it will not clog the xylem and rot because the sand cant enter xylem and hydrogen sulfide can be safely oxidized around rooting areas. Plant roots also prent the clogging of the sand pillar and the pillar can slowly generate miniscule amount if co2 in the water and the root zone.