Aquarium plants do poorly and even die in fish tanks for many reasons. Tanks must have a balance of light, carbon dioxide, appropriate substrate and nutrients for the plants to thrive. The plants will prosper by correcting a few of these conditions.
Most aquarium plants need sufficient light to grow. If the tank lights are not strong enough for the size of the tank and the amount of plants, then the plants may begin to die and rot.
Carbon Dioxide (CO2)
Plants need CO2 in order to accomplish photosynthesis, and even though fish produce small amount of CO2, it may not be enough for the plant. CO2 canisters or any other type of CO2 system can be bought and used to introduce CO2 into the fish tank.
Many aquarium plants need a small substrate to root in that is around 1.5 to 3 m. The small size will allow proper water flow to the roots. Various plants may need different types of substrate.
Nutrients such as phosphate, nitrogen, potassium, iron, nickel and zinc are necessary for healthy plant growth. Fish and fish food produce many nutrients, but if there are not enough for the plants to live on, aquarium fertilizers can be used.
Disease can kill aquarium plants, as well as the fish in the tank. New plants should always be cleaned before introducing them into a tank.