Diana Walstad’s “Ecology of The Planted Aquarium” has been the standard guide to Low-Tech Aquariums since its first publication in 1999. This book has stood the test of time in the aquarium world because the content presented in the book continues to remain true. The Aquarium Hobby is constantly changing and improving (filters, lighting, equipment etc). To have a book that has “stood the test of time” with no alteration of content is not a normal occurrence in the always changing aquarium industry. Walstad is a large advocator of the “balanced” aquarium approach. In doing so, she presents that aquariums are extremely small representations of a natural environment.
Walstad suggests that plants can survive from a nutrient based substrate and feces from the fish. The plants and fish then establish a symbiotic relationship in the aquarium. The fish eats food provided from the aquarist and then the waste settles to the bottom and provides the plants with nutrients to grow. The plants in turn, act as a water purifier by absorbing unwanted chemicals or toxins from the water column (ex. Ammonium). She also encourages the utilization of floating plants such as Giant Duckweed for the diminishing of toxins and heavy metals. Provided in the book are examples of research showing the harmful effects that can result whenever a fish is exposed to water with a very heavy amount of Zinc, Lead, Copper etc. (juvenile mortality, stunted growth, & egg fragility).
There have been many famous aquascapers and planted tank keepers who are in favor for the balanced aquarium approach including, Dustin Wunderlich and David E. Boruchowitz. Walstad’s main argument is that utilizing plants in a natural approach is the easiest approach in comparison to high tech planted aquariums. She personally does very little water changes (because the plants purify the water), provides no added NPK or other liquid fertilizer schedules (because of the fish waste), and suggests that keeping a low tech aquarium can keep fish happy, healthy and breeding.
This book features a plethora of topics that were not discussed in this article that will help you understand the plants on a biological level and at a hobbyist level. One of the largest problems that a lot of aquarium keepers have is experiencing the rapid growth of algae. One method that I found helpful was using plants that intake nutrients at a high rate. Whenever you use plants that absorb nutrients quickly, there is little “food” left for the algae to take in and grow. There are other aquarists who support this method for example, Gary Lang (Rainbow Fish Expert & Vice President of The Missouri Aquarium Society (MASI)), uses Water Wisteria (Hygrophila Difformis) to keep algae at bay. Walstad uses floating plants because they do not need to absorb CO2 from the water column, rather they can simply absorb it from the air.
This book has stood as a guide for the traditional aquarium keeper and the expert since 1999. It was also not composed in haste as it used counsel from 10 representatives of different universities, some of which, were from non-English speaking countries (Germany, Spain, Italy). There has been a rise in high profile aquariums in the last ten years. Arguably the most famous aquascaper of all time, Takashi Amano, has shown the world the high-tech approach of plant keeping but few have seen the ‘balanced’ approach that has been utilized by aquarists and local fish stores for decades. The content of this article is a tiny portion of the information and topics discussed in comparison to Walstad’s writings. If you would like to learn more on producing a beautiful planted aquarium then I would highly encourage you to purchase and read the book.