Keeping Aquarium Plants

By Al Ridley
First published in the newsletter of The Kitchener-Waterloo Aquarium Society, Canada

I was surprised at the number of people that approached me last meeting about plants. I have always enjoyed keeping them as have several of my hobbyist friends but there never seemed to be much passion with the exception of a couple of people. In this article I will tell you a little about keeping and growing plants successfully, or at least what makes it successful for me.

First of all, let's discuss the need for plants in the aquarium. An aquarium without plants is like a home without furniture. It is liveable - but ugly, uncomfortable and inefficient. Live plants aid in displaying fish giving them shelter and security. They provide shelter for baby fish, shy fish, weak fish and females giving birth. They serve as food for vegetarian fish. They help prevent green water by competing with the algae for nutrients in the water. Plants absorb carbon dioxide and wastes and add oxygen to the water. They increase the surface area for algae, tiny worms, rotifers and protozoa to grow and in turn provide live food for the fish in the tank. And you thought that they just looked nice.

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.

What do I like about potting my plants? I guess the biggest thing is that like most plants, they do better if you leave them alone. Potted plants can be moved around easily without disturbing the root system. I have a Cryptocoryne wendtii that has been potted for almost four years now. It goes through stages of fullness and dying back but always seems to do well. There will come a time very shortly that I will remove the plant, separate the runners and replant it in many other containers. Once the pot becomes root bound (you will see the roots growing upwards out of the pot), the plant needs to be repotted.

Lighting is the most important prerequisite for successful plant growth. I have heard many different opinions on how much light is needed but my rule of thumb is one and a half watts per gallon. Most of my tanks are on home made stands that have the double four-foot fluorescent strip over them. I have two aquariums that are on their own stands, My 180 gallon aquarium has two, double four foot fluorescent strips (160 watts) and my 50 gallon has one, double four foot fluorescent strip (80 watts). I use the regular Cool White tubes, that you can buy relatively inexpensively at most hardware stores, along with the Plant and Aquarium tubes that sell for around $6.00 at the same stores. Most store bought canopies are not capable of providing enough light to keep most aquarium plants healthy so be sure to ask your store dealer for suggestions if keeping plants is your focus.

I have also experimented with different types of lighting. I have had good success with both compact fluorescent bulbs and par 20, 50-watt halogen bulbs. Don't be afraid to try different light sources. Plants will recover very nicely even if they look rough.

Pruning your plants will also help them to grow healthy and strong. Carefully remove dead or dying leaves and any leaves that are damaged or have holes in them. The plant uses a lot of energy to try and repair these leaves, energy that could be used to produce new, lush growth.

If your goal is to keep a natural aquarium, live plants are a must. If you just want to have a nicely decorated aquarium, live plants can be used with plastic plants and rocks to beautifully aquascape your aquarium. Remember that the key is to be patient and to provide the right conditions for the plants that you are keeping.