By Robert Paul Hudson
While much attention is brought to methods in aquatic gardening that involve high tech devices such as C02 systems and intensive lighting because ethey produce rapid growth in plants, there is another methodology often referred to as “low tech”. This approach to planted aquariums has often focused around the book Ecology of the Planted Aquarium by Diana Walstad. I had an opportunity to speak to Ms. Walstad.
Ms. Walstad received a B.S. in Microbiology from the University of Kentucky (Lexington) in 1968, and says she was born into a family that always had aquariums and ponds. Other than a brief stint in the Peace Corps, she has worked as a research technician all her life. “I worked in several medically related fields for the University of North Carolina (Chapel Hill) until 2001. Currently, I am working for the federal government as a cell biologist in a much more esoteric field- intracellular signaling.”
For someone who has not read your book, please briefly describe what the main points and objectives are.
The overall goal of this book is to get aquarium hobbyists to better appreciate plants. Plants aren’t vital for fish survival, but they can still play an important role in the aquarium. For example, plants keep algae in check, take up toxic ammonia, recycle fish food wastes, and oxygenate the substrate. Plants reduce the need for frequent water changes and gravel cleaning while still keeping the fish healthy.
The book also explains how plants affect the aquarium ecosystem and what factors affect the plants. For this I use scientific information that few hobbyists have ever seen. Then I describe my own aquariums and “my method”. However, I’m much more interested in providing information that hobbyists can use to set up their tanks the way they want. To this end, many hobbyists use the book’s information to better maintain their High Tech planted tanks.
I understand Ecology of the Planted Aquarium was the culmination of many years of work. Could you describe the process, what first inspired you and what your original goal was for the project?
Believe me, there was no planned project to write a book. The process really started in 1988 when I decided, after a long dry spell without tanks, to once again set up an aquarium. This time I was determined to have a planted tank. All past attempts had failed, so this time I decided to try something different- use soil in the tank. Ironically, I was inspired by a 1988 FAMA article (“Magic Touch or Common Sense?”), which was an interview with the plant enthusiast Dorothy Reimer. She described using potting soil to get spectacular plant growth. When I too used potting soil and got spectacular plant growth, I was converted. I also noticed that my fish were doing very well in these tanks with minimal tank maintenance. I decided to try writing narrowly focused articles based on scientific information. Thus, I wrote many articles for FAMA and TAG (The Aquatic Gardeners Association) on the preference of aquatic plants for ammonia (not nitrates), allelopathy, submerged soil chemistry, fish food as a source of plant nutrients, etc. The positive response from readers kept me going. Eventually, these articles would become chapters (or sub-chapters) of the book. At some point, I wondered if I could mesh all the magazine articles I’d written on so many seemingly unrelated topics (allelopathy, ammonia preference by plants, metal toxicity, etc) into a book. I decided that it could be done, and more importantly, that it was worth doing.
Did it evolve as you envisioned or were there any surprises?
There were many surprises. Every scientific paper might have a new surprise. It was exhilarating. There were days when I couldn’t wait to get to the libraries. The little experiments I did also provided some surprises, like finding less plant growth in potting soil with added fertilizers than without added fertilizers. It’s empowering to do experiments to test out a theory. When I plan an experiment, I am often spurred on by the realization that I might discover something that no one else in the entire world knows.
The big surprise, not as much fun, was my experience with book publishers. It seems my book wasn’t academic enough for university libraries but it was “too scientific” for hobbyists. I spent a couple of frustrating years trying to find a publisher. If I had finally contracted with the university publisher that was interested, the book would have been severely condensed, cost $70, and would be purchased by only a few academic libraries. Certainly, no interviews for FAMA! I ended up publishing it myself, so that it came out exactly the way I wanted it.
The hobby has changed in many ways since you first began your research. Do you think the hobbyist today is attracted to the principles of your book for the same reason you originally intended?
Yes. I think hobbyists are attracted to the concepts in the book for the same reason that I was. These concepts also have real world applications. For example, we’ve all read about environmental efforts to use wetlands to clean up waterways. In my book, I advocate using floating/emergent plants in aquariums to control algae. Both things are based on the “aerial advantage”- that all floating/emergent plants (i.e., wetland plants) can use air CO2 that algae doesn’t have access to, are prodigiously fast-growers, and can quickly drain nutrients from the water.
Your methodology is often described as a low-tech approach. I do not see it in that simple of terms. I see it as attractive for the challenge of applying the scientific principles and seeing the effort come to fruition, rather than simply an approach to avoid the cost of high tech equipment. Your most avid followers seem to have a passion that goes far beyond just saving pennies. Is that an accurate observation that you feel compliments the intent of your work?
Yes. I think you’re right. I’m delighted that people see my book as more than just saving pennies. Aquariums are truly fascinating. They have so much to teach us.
Diana feels her work on the subject is complete other than small future updates to the book. Betty Harris of Norman, Oklahoma found the book two years ago and says “It is chock full of scientific information on the ecology of planted tanks.” She feels the book has made a tremendous difference. “ It’s made keeping plants happy easy! You don’t have to tinker with water fertilizers or add CO2. Just add soil, plants, supply a decent amount of light and you’re set,” she exclaims. Betty has even set up information on a WEB page that provides a summary of the book’s methods as well as a step- by step demo of a tank set up. http://thegab.org/Articles/WalstadTank.html
While some Walstad followers contend any aquarium plant may grow well with this methodology, there is an assumption that slow growing rooted plants will thrive more than very delicate and more finicky stem plants. I will focus on two such plants that deserve to be in the spotlight.
Nuphar japonica
From lakes and rivers in Japan, the light green almost translucent leaves make this water lily an especially decorative plant in the aquarium. It grows from a thick creeping rhizome that looks like a chunk of raw pineapple. The growth is slow so that it is easily managed and rarely do the leaves reach the water surface when lighting is more subdued.
Sagittaria subulata
Called “dwarf sag” this grass like plant grows easily in the aquarium with little effort. Above the water the leaves take on a spoon like shape. Underwater the plant reaches a maximum height of about six inches and may be trimmed to maintain a shorter height.
Both of these plants are a worthy addition to any freshwater aquarium and thrive with little special attention
