"In general, aquatic plants seem to do well in a variety of soils-clays or loam soils with some organic matter. Indeed, I haven't been able to find any major or consistent difference in plant growth in various ordinary soils. . . . In most instances, substrate fertilization appeared to be either detrimental or not helpful. Best plant growth (under aquarium conditions) often appears to be not in the most fertile soil, but in the one that is the least toxic." Ecology of the Planted Aquarium, p 132.
So many people ask questions about which soils are suitable for use Walstad aquaria, it seemed time to start a thread on just that topic. Here is where we can share our results using different soil substrates.
First, some definitions. "Soil" has different meanings to different people. For our purposes, "soil" means any growing medium intended for terrestrial plants, but which we have adapted for use in the planted aquarium. "Topsoil" has a very specific meaning to soil scientists, horticulturists, and geologists. Often, what is labeled "topsoil" in a bag in your garden center bears no resemblance to natural topsoil as understood by science. Most natural topsoil is primarily minerals, with only a small percentage of organic matter. In our discussion, we should use the general term topsoil to refer to naturally occurring surface soil. When we are talking about a specific commercial product that has "topsoil" as part of its name, we should be sure that is understood.
Another term that needs definition is "organic". In this discussion, organic is used in the scientific or chemical sense; that is, material derived from living matter. This organic matter will be in various stages of decomposition. When I use the term "organic" I am not referring to the organic method of gardening, and I most definitely do not mean the undefined marketing hype used to sell so-called "natural" products.
And one last bit of clarification, when we talk about soil in this discussion, we are not referring commercial brands of aquarium substrates, like Flourite, Eco Complete, ADA Aquasoil, etc. Some of these products are very good, and may be useful in the Walstad method. Some are not.
I will start the discussion in the next post. But the only way that this thread can become really useful is if you post your knowledge, experience, and questions too!
So many people ask questions about which soils are suitable for use Walstad aquaria, it seemed time to start a thread on just that topic. Here is where we can share our results using different soil substrates.
First, some definitions. "Soil" has different meanings to different people. For our purposes, "soil" means any growing medium intended for terrestrial plants, but which we have adapted for use in the planted aquarium. "Topsoil" has a very specific meaning to soil scientists, horticulturists, and geologists. Often, what is labeled "topsoil" in a bag in your garden center bears no resemblance to natural topsoil as understood by science. Most natural topsoil is primarily minerals, with only a small percentage of organic matter. In our discussion, we should use the general term topsoil to refer to naturally occurring surface soil. When we are talking about a specific commercial product that has "topsoil" as part of its name, we should be sure that is understood.
Another term that needs definition is "organic". In this discussion, organic is used in the scientific or chemical sense; that is, material derived from living matter. This organic matter will be in various stages of decomposition. When I use the term "organic" I am not referring to the organic method of gardening, and I most definitely do not mean the undefined marketing hype used to sell so-called "natural" products.
And one last bit of clarification, when we talk about soil in this discussion, we are not referring commercial brands of aquarium substrates, like Flourite, Eco Complete, ADA Aquasoil, etc. Some of these products are very good, and may be useful in the Walstad method. Some are not.
I will start the discussion in the next post. But the only way that this thread can become really useful is if you post your knowledge, experience, and questions too!