Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
Jnad, I see you are from Norway. Are the labels of these products in English, or are they a translation?
There are 2 components to soil, and each of these can be further defined.
A) Organic matter. Leaves, animal waste, microorganisms, macroorganisms.
B) Mineral component. Sand, Silt, Clay, Rocks. These are particle sizes, and say nothing about their chemistry.
Organic matter such as leaves and manure continues to decompose, becoming fertilizer and nutrients for the plants, serving as food for beneficial microorganisms, and altering the soil chemistry. Highly desirable in the garden. Can work in an aquarium, but there are some cautions. The basic question in both garden and tank is: What happens to this stuff once it is in place?
If the results are bad, then do not use it in that quantity. Perhaps use less or perhaps none.
Mineral types of materials do not break down the way organic matter does. Rocks, sand and silt may be neutral in the water, do nothing, or they could dissolve and alter the water chemistry. This is especially noticeable if the rocks etc are of a limestone origin and the tank water is very soft and acidic.
Clay sized particles are active in the water, and clay is especially well thought of for garden and tank because of its cationic exchange capacity. This means it can hold fertilizers and minerals in a way that they are available to the plants, but do not get loose into the water column.
Product 1) Uses terms in a bad way, trying to hide or at least confuse the issue. (Maybe this is in part because it is a translation) In my opinion, based on what I see in the first post, this is a soil amendment, not a soil. It contains one ingredient that has been shown to create problems in aquariums (cow manure).
Product 2) Has too little info to make a determination. If there is any way of getting about a cup or two (quarter to half a liter) there are some tests you can do to see if it is useful in an aquarium.