I've read that you need a substrate in order for plants to grow, so how do I add substrate/clay/soil to an aquarium already full of fish?
There are a wide variety of substrates for use in today's plantedaquarium. Due to the growth and popularity of aquatic plants, new productsare being introduced all the time. This is good for us gardeners, but itonly adds to the confusion of which type is best. These new varieties, alongwith the old standards, has given us many different choices. Somepeople stick with the proven recipes, while others experiment with newand sometimes untested ideas. A lot of real world data exists to substantiatethe viability of commercial substrates and additives, as well as homemadepeat, vermiculite, or soil blends. It's all up to the needs of the individualaquarist. Some like the simplicity of commercial products while othersenjoy preparing the substrate they believe to be most productive.
Only a few of the dozens of types of atoms and moleculesnecessary to plant growth need be of concern to aquarists. Most arereadily supplied by fish food and wastes. Except for newly planted and"boosted" systems with intense lighting, carbon dioxideinfusion and soil augmentation, most folks can and should avoidchemical supplementation. If you're in the "booster"category, know what you're doing and stick with regular testing andmaintenance, particularly frequent, partial water changes.
ST International Aqua Soil for Aquarium Plants, 4.4 Lbs ..
How to Make Your Own Aquarium Soil - Pets
I prefer to pot most of my plants. The method is very simple and does not take a lot of time or effort. First you need some sort of pot. This could be the plastic pots that your garden plants come in, yoghurt containers, the bottom cut off a plastic pop bottle or small clay pots that you can buy at most nurseries. If it is a plastic container, make sure that it is not toxic to your plants or fish. Next get a bucket and add some water to it. Into the bucket add some potting soil. I prefer to use Hillview Potting Soil as I have found that it is pure soil with nothing added. The reason for mixing the soil and water together first is that if you do not saturate the soil and drop the pot into the aquarium, you take the chance of the air in the soil exploding to the surface and making a real mess of the aquarium. Believe me when I say that it can be very frustrating if you rush the job and end up with a big mess. It has happened to me too many time to count. Once the soil is moist (not like soup, more like Play Doh), fill your potting container 2/3rds full of soil. Take your finger and push it into the soil to create a small planting hole. Take your plant and carefully insert the root system into the hole. Carefully fill the hole from the sides, then add aquarium gravel to top up the container. Gently pull the plant upward until the crown of the root is just visible at the gravel surface. I usually have a bucket of aquarium water close by so that I can now submerse the potted plant for a few minutes prior to adding it to the aquarium. This will allow any trapped air to escape and possibly prevent the grief that I was talking about earlier. Now you can place the potted plant into the aquarium and enjoy. The potting soil will give the plant that extra goodness and it shouldn't be too long before the plant begins to thrive and propagate.Why's this important? Most of the aquatic (andterrestrial) plants we grow do best in loamy soils. ; no joking; clay-diameter material acts asa colloid, attracting and slowly releasing water and nutrients. Youneed only use a small amount of clay to gain the absorptive property ofits vast surface area. What about the gravel/sand we call substrate?For our purposes here we will consider the inorganic mineral substratesas not contributing nutriment to aquarium plants.