I think Nick hit the nail on the head, and jamila makes a fair point, which colour do you prefer?
Both products appear to lower ph and kh, the scapers soil is more nutrient focused on plants, so probably contains small amounts of ammonia and possibly other nutrients.
If you plan to water column dose with sufficient fertiliser then I'd assume either one will be fine.
Taken from dennerle Web site.
SCAPER'S SOIL
- Nutrient substrate for strong plant growth
- With all essential minerals and trace elements
- With fertile volcanic soil
- With bio-filtering function for healthy, clear water
- Actively creates soft, slightly acidic water (approx. pH 6-6.5, KH 0-2 °d)
- Twice-baked – lasting water stability
- Ideal in combination with CO2 fertilisation
- With valuable humic and fulvic acids
- Ideal for plants, fish and shrimps that require soft, slightly acidic water.
SHRIMP KING ACTIVE SOIL
- The irregular shaped grains, with a diameter of 1-4 mm also give a natural appearance
- The dark black colouring provides excellent contrast with the vibrant colours of the shrimps
- Porous surface for the settlement of important cleansing bacteria
- Also extremely well suited to use with substrate filter systems
- Does not discolour water
- Promotes growth – bacteria, single-cell organisms, single-cell algae and other microorganisms - as valuable, natural nutrition, especially for young shrimps
- Excellent filter capacity for crystal-clear water
- Binds harmful substances for healthy living conditions
- Also ideal for all tropical fish and plant species that like soft, slightly acidic water
- Does not promote algae
- The use of ShrimpKing Bee Salt in combination with osmosis water extends the useful life of ShrimpKing Active Soil
ShrimpKing Active Soil consists of up to 100% natural raw materials. Produced from a variety of carefully selected natural soils, it provides essential minerals and trace elements, which promote the health and growth of shrimps.
ShrimpKing Active Soil has been developed especially for the successful keeping and breeding of shrimps. It is particularly suited to all species that like soft, slightly acidic water, especially bee shrimps, such as the popular Crystal Red, Red Bee, Tiger Bees and Shadow Shrimp.
It adjusts the water to be more like that which soft water species are accustomed to in their natural habitats. As a natural ion exchanger it reduces the pH and stabilises it at a slightly acidic level (approx. pH 6.0-6.5). At the same time it reduces the carbonate hardness – down to close to approx. 0-2 °d CH depending on the water source - and thus makes the water considerably softer.
It also serves as a natural source of humic and fulvic acids, without discolouring the water.
Cheers.
