Substrate

In nature, plants are continuously receiving nourishment from their surroundings.
Aquarium plants derive nourishment from the substrate. There are different varieties of
substrate available now, but for the beginner a substrate that is low maintenance and
stable is the ideal choice. A substrate that needs constant watching and gets messy is not
recommended. Similarly, a substrate that is capable of changing the water chemistry is
also something to keep away from. This kind of substrate will require constant
monitoring of the water. Organic substrates, rich in nutrients, will mess with your water
quality and give out excess nutrients.
Since the substrate lies at the very bottom of your aquarium, it is difficult to change it
once the aquarium has been established. So, in many cases you are stuck with your
substrate for a long time. That is why you need to be wise when you choose it. Ideally,
you should select a substrate that is inert and that will not alter your water chemistry. The
perfect substrate will also have a high Cation Exchange Capacity. The Cation Exchange
Capacity refers to the ability of the medium to absorb nutrient ions. Simply put, this
means that your substrate will hold on to the nutrients and make them available to plant
roots.
In this respect, sand is a very poor substrate. It has none of the qualities described above.
It can be used only as an anchor for your plants. Gravel will usually also have a very low
Cation exchange Capacity and some types of gravel will alter the water chemistry.Fluorite is a great substrate. Though it is a bit expensive, it is very nice looking and
nutrient rich. It will not get soft when in water. It also has iron and other trace elements
that are good for your plants. Vermiculite is a soil additive that is very rich in nutrients,
but it is also very light and needs to be placed below a layer of heaver material.
Otherwise, it will start floating around and make your water cloudy.
Using suitable additives in your substrate will be beneficial to plants. Commercially
available products help to induce plant growth. Some of these are to be mixed in with
water, while others need to be pushed in near the roots of the plant. You will find more
detailed information about plant nutrients later in this e-book.
Do NOT use peat moss, bagged potting soil or compost in your substrate. These will
decay after some time and prevent root growth in plants. A soil that has only a little
organic matter and has a higher concentration of fine clay particles is best suited for plant
growth.