One of our fellow club members has a problem many of us would like to have. His Amazon swordplants grow too large for his 50-gallon tank and he has to get rid of them periodically! One of his monster plants was on auction last May, and it was very impressive. It was a beautiful melon sword (Echinodorus osiris) with a flowering stalk. He kept some of the plantlets from the stalk and they are growing quite well.

So what’s his secret? It is a combination of many factors, the primary ones being quite basic. His plants get good light and proper fertilization: macro-nutrients, micro-nutrient supplements (mainly iron), and carbon dioxide.

The tank is illuminated by three 20W GE fluorescent plant lights, lit 14 hours per day. The lights sit over the glass cover and are controlled by a timer. The plants are close to the lights and have a regular day and night cycle. The plant lights have a spectrum geared towards healthy growth and yet their colour is close enough to white light that the fish don’t look weird when viewed under them.

The gravel is smooth and on the larger side (over 5 mm). The large-sized gravel looks good, but it has the drawback that uneaten food and fish waste can accumulate in the gaps between the grains. In a fish-only tank, this means lots of vacuuming to keep the substrate from going anaerobic and creating problems. On a planted tank however it can be quite beneficial. All this waste is plant fertilize; the macro-nutrients I mentioned earlier. Amazon sword plants and many other plants with an extensive root growth are heavy feeders. They develop extensive root structures in this substrate, keeping it from going anaerobic and breaking down the fish waste.

Another factor is micro-nutrient fertilization. If you look at the soil in the tropical regions you will notice that it is often reddish in colour. This is caused by the presence of iron and manganese. In some areas there is so much iron that it precipitates as a rusty dust on the bottom of the streams. Our tap water, in comparison, is lacking in iron, so we must add it to our planted tanks. One sure sign of iron deficiency is a glassy, yellowish, look to the plant leaves. Once iron is added, the leaves turn bright green and grow larger. A little goes a long way with micro-nutrients, so make sure you use a commercial preparation for aquarium use, or buy an iron test kit and use iron chelate.

Last but not least is carbon dioxide. During the day the plants use it up when building their cell structure and return dissolved oxygen to the water. The carbon dioxide here is provided by simple yeast fermentation. A four-litre carboy with stopper and tubing leads to an airstone inside the tank. It contains a solution of sugared water and bread yeast, and can provide carbon dioxide for four to six weeks before replenishment.

The whole tank is filtered by an Aquaclear Mini, and is well stocked with fish and plants. Though the filter is undersized for the tank, it provides valuable water movement that circulates nutrients. The lush plant growth contributes greatly to the water quality. This setup requires regular bi-weekly water changes of ¼ of the tank’s volume.

Keep in mind that Liebig’s Minimum Law governs plant growth. That means that the growth factor present at a minimum determines the growth rate. This is called the limiting factor. In this setup the limiting factors are carbon dioxide and iron. Leave out the carbon dioxide and the plants stop growing. Leave out the iron supplements and the leaves become chlorotic (the glassy yellow look). Lights can also become the limiting factor if not changed often enough (fluorescent), or are not bright enough. If you would like to try carbon dioxide fertilization, the yeast recipe is the most inexpensive way. Many experts think it is a waste of time and money on the long term, but if you don’t want to mess with high-pressure cylinders, valves and regulators, it is the safest alternative. Here is the recipe I use, adapted from one in the rec.aquaria FAQ on the Internet:

• Put four cups of sugar in a four-litre carboy.

• Fill with water up to the point where the width starts tapering to the neck. Stir or shake well until it is all dissolved. Be careful not to spill the whole thing.

• Dissolve ¼ of a teaspoon of baker’s yeast in a little bit of warm water. Pour it into the carboy and stir well.

• Put the stopper in the carboy and it should start bubbling almost right away. By the next day the pressure would have built up enough to bubble in the tank. If it hasn’t, look for leaks.

Some people recommend using pop bottles, but I found that it is very hard to get an airtight seal in them once one drills a hole in the cap for the air tubing. Silicone does not stick well to plastic, and any little leak usually means no bubbling in the tank. The carboy and stopper work much better.

Before experimenting with carbon dioxide fertilization, make sure your tank is well-planted and under-stocked. Even in a 50-gallon tank, the above setup can cause sudden shifts in pH when the carbon dioxide is first started or suddenly stopped. This can be stressful to the fish. Also, insufficient light or insufficient plants may result in higher than ideal carbon dioxide concentrations in the water, again stressing the fish. Therefore I recommend that such fertilization be done after the tank has had time to settle, and it is running well. Then you can watch your plants grow without worries.?

When I started my first aquarium in Calgary my friends were always amazed that I had real plants in it. That made me feel really good for back in Brazil, where I got started in the hobby, aquarium keeping was very low-tech and aquarium keepers relied on live plants to help filter their water. Everyone had live plants in their tanks, and the stores did not carry plastic ones (or if they did, their price would have been prohibitively expensive given the import restrictions of the time). Something that was second nature to me in the past was now considered to signify a level of expertise.

Many years later I joined the Calgary Aquarium Society and heard of the HAP program and how some club members had their aquatic plants flower, and some had actually propagated their plants from seeds. I realized then that I wasn’t such a hot shot after all for keeping Amazon sword plants alive and growing Aponogeton plants from bulbs. It was quite humbling from me to hear from the HAP masters on their latest feats with their aquarium plants.

Let me assure you that most of the aquarium plants available today are capable of flowering. It is quite natural for them to do so, and they will do it in an artificial setting when conditions are right. Some flowers are very pretty, others are barely noticeable, but one thing I’ve noticed with many of them is their short life – sometimes as short as one day or less. If you know your plant is about to flower and you want to enter it for HAP points, make sure you have a spotter on call or be ready to take a picture

So what is the secret? I don’t have a formula for making my plants flower, but I’ve noticed a couple of things. First is light. Without proper lighting the plants don’t grow well, much less flower. There is a certain level in which the plants do well and grow. If your light intensity increases past this level your plants should flower and grow vigorously providing they are established and you don’t have an algae problem in the tank. Regular light and dark periods are important too. Some people claiming that their plants flower when the light period is increased (up to 14 hours). I find my plants flower in winter, when the aquarium gets a few hours of sunlight on the front pane. I don’t change the light period (it stays 12 hours) but the light intensity changes dramatically with the sunlight.

Another factor seems to be plant mass. I once let star grass (Heteranthera zosterifolia) grow out of control in a corner of one of my tanks. It formed a tangled mass of plants growing all the way to the surface and actually running along the surface for half their length. Then the growing tip of the plants bent upwards and grew out of the water, producing tougher leaves and two flower buds per tip. This went on for a couple of months (January and February) and there were blooms every day. The plants’ mass could simply be an indication of the plants’ health (and therefore their ability to flower) although there is some evidence that plants do better when there is a large number of the same species together.

The third factor is nutrition. It takes energy to produce the flowers, and with some plants you can actually control the amount of flowers with fertilizer. Water lilies are an example. They need root fertilizer to flower well.

So if there is a formula to make aquatic plants to flower it must be:

flowers = healthy plants + light of proper intensity and time + nutrients

It is important to note that the majority of aquatic plants produce aerial flowers, so the plant will either grow to the surface or it will send flower stems up to the surface. A deep tank may prevent you from getting flowers because of the water depth. In this case you can try lowering the water level. The other dimensions of the tank are not at all important, just make sure the plant is not cramped.

As I said earlier, most aquarium plants are capable of flowering. As with anything in life some things are easier than others, and some things are impossible. Ferns are not flowering plants so don’t expect Java fern (Microsorium pterops) or water sprite (Ceratopteris thalictroides) to flower. The most they will do is produce spores under their leaves. On the other hand, some plants that one may not immediately think of as flowering plants in fact are. Hornwort (Ceratophyllum demersum), Cabomba, and duckweed (Lemna minor) are three examples.

Here are just some of the plants that have produced flowers for various CAS members:

In the pond: water lilies (Nymphaea spp.); water poppy (Hydrocleys nymphoides); arrowheads (Sagittaria spp.); frogbit (Hydrocharis morsus-ranae); umbrella palm/papyrus (Cyperus spp.).

In the aquarium: Vallisneria spp.; temple plant (Nomaphila stricta); Cryptocoryne affinis; Amazon swords (Echinodorus spp.); many of the Aponogeton species (including the Madagascar lace plant); hornwort (Ceratophyllum demersum); Anubias barteri.

If you would like to get an aquatic plant to flower, it is best to start with the easier ones. For a pond, just about all the plants available in the pond section of garden centres will flower. But avoid placing tropicals outdoors because they don’t like our local temperature fluctuations. For an aquarium, start with Aponogeton or star grass, but just make sure you have bright lights. Good luck. ?

Most of our tanks are tropical, and so are our aquarium plants, but have you ever taken the time to look at our ponds and rivers and see what grows there? I did just that last year and I am amazed at what grows almost literally in our backyards and goes mostly unnoticed.

I had decided to try setting up a water garden in a half-barrel, so as part of the preparation work I purchased two books on water gardening and did some outdoor research. The latter was to accommodate two of my preferences: being outdoors whenever possible and valuing our native plants over more exotic or cultivated varieties. Well, I was very impressed with the selection, even out here in the prairies. A lot of the water “weeds” that boaters and fishermen are not so fond of make good pond plants. Some have even found their way into our aquaria or are related to our tropical aquarium plants.

Two very familiar plants are the common duckweed (Lemna minor) and hornwort (Ceratophyllum demersum). Yes, the very same hornwort we use in our aquaria grows profusely in many of our lakes and you will be amazed at the sizes it can reach. As for duckweed, just about any large-sized puddle will have it in abundance.

We also have one species of Sagittaria, the arrowhead. It grows in lakes, creeks and even roadside ditches. This is Sagittaria cuneata, a beautiful plant with ribbon-like submerged leaves and arrowhead-shaped aerial leaves. The flowers are usually in groups of three, have three very round petals with a yellow center in the male flowers. These flowers rarely last more than one day, but are in a flowering stalk with a few groups so the blooming period can span over a week. The plant stays small, up to 40 cm, and likes shallow areas.

Also common around our area is the bur-reed (Sparganium sp.). It looks like a cross between an arrowhead and a cattail. The flowers are very small and the fruit resembles a burr. It likes shade and makes a reedy margin on a pond.

We also have a water lily of sorts. That is the yellow pond lily or spatterdock (Nuphar variegatum). This plant grows too large for smaller ponds. It has heart-shaped leaves and yellow flowers. I have seen another plant with it that has floating leaves like a water lily, but I could not identify it from my books.

The water milfoil (Myriophyllum exalbescens) is also fairly common. Pond keepers are familiar with a related plant, the parrot’s feather (Myriophyllum proserpinacoides). Another species has become a pest: the Eurasian water milfoil. I would think twice about taking a clipping of any milfoil species from the wild, and most definitely would not “release” the plant elsewhere. You never know if what you see is one of our native species or the Eurasian introduction.

Lastly are the many reeds and rushes. My books don’t have much information on these except for the ubiquitous cattail (Typha latifolia). Our native cattail grows too large for a small pond, but it looks great in a large pond, and you could try growing it from seeds for some extra challenge!

So where are all these plants? The best places to see them are in our national and provincial parks, where plant collecting is strictly forbidden. There is one form of collecting that is actually encouraged in our parks though, and that is of information and knowledge. You can see what grows, where and how. You can also get great aquascaping ideas for your pond or aquarium. Outside these parks, keep your eyes open for roadside ditches on your way back, I don’t think anyone will mind if you take a small arrowhead or bur-reed for your pond. You will get muddy and feed a few mosquitoes though.

The best location for observing aquatic plants is Cypress Hills Interprovincial Park, on the border with Saskatchewan in southeastern Alberta. There is a boardwalk on Elkwater Lake that takes you through the cattails and you can see arrowheads, hornwort, milfoils, duckweed, and reeds. A short hike from Spruce Coulee dam takes you to a creek that is overgrown from shore to shore with arrowheads. It is quite a sight.

Around Calgary, the Bow River has crisp-leaved pondweed (Potamogeton crispus) on its shores. Glenmore Reservoir, particular the west end (The Weaselhead) and the Inglewood Bird Sanctuary ponds, are good places. The Cave and Basin area in Banff has some interesting vegetation also.

To the north, Crimson Lake, just outside Rocky Mountain House, has extensive beds of spatterdock on its south shore. It also has marsh marigolds (Caltha palustris), arrowheads, milfoils, and cattails.

If you would like to hear about my water gardening experience, come to the April meeting. I will be discussing how to set up water gardens and I would love to answer your questions and share some experiences.

REFERENCES:

Water Gardens, David Archibald and Mary Patton (eds.).

Calgary’s Natural Areas

, Harold W. Pinel (ed.)

Wildflowers Across the Prairies

, F. R. Vance, J. R. Jowsey, J. S. McLean.?