John C., Walch
15042 N. Moon Valley, Dr.
Phoenix, AZ 85022
PH: (602) 548-8697 FAX (602) 862-9061
Thank Rick Martin, Mikki, and the rest of the organizers of WMC 97 for the invitation to participate in this exciting conference.
1997 is "The International Year of the Reef" and the theme of this conference.
Maintaining an enclosed marine ecosystem is an excellent way of sharing the secrets of life on a coral reef. I have noticed that children in contact with marine life have a heightened concern for the marine environment. While not everyone has the means to travel to see coral reefs first hand, exposure to reef aquaria in the classroom or in private homes may increase future generations sensitivity for the protection of the worlds reefs.
The present status of the marine aquarium keeping hobby still relies on the majority of the ornamental marine organisms being collected from the tropical oceans. Whether or not WE believe that this industry in anyway contributes to the degradation of the coral reef, our hobby appears to many as a destructive enemy of the reef.
However, I would like to congratulate the hobby on its strong interest and genuine concern in moving towards some degree of self-sustain ability. A diligent effort by aquarists to purchase cultured marine-life, self imposed "Eco- Labeling", organizations like AMDA, and the increasing attendance to conferences like this one, all indicate an alternative ecological movement. It is imperative we keep the momentum moving forward by sharing information and technological advancements in the field of Ornamental Mariculture to help insure the longevity of the hobby.
The concern for the environment and the educational values and pleasure derived from maintaining a captive marine ecosystem has always been a complex decision for the marine aquarist. With the availability of cultured marine-life this in no longer the case.
While the term "MARICULTURE" may be relatively new to some aquarist the concept certainly is not. Terms like, tank raised, captive breed, cultured, propagated, maquaculture, etc., maybe more commonly used. Mariculture is the correct word for the saltwater version of freshwater Aquaculture. Ornamental mariculture is more specifically the controlled culturing and propagation of a wide variety of ornamental marine plants, fish, and invertebrates as opposed to food Aquaculture or food mariculture
"1997 The International Year of the Reef", has generated national interest in Ornamental mariculture. I was recently in Palau as a member of the US Dept. of State advisory counsel to the Palau government.
Our mission was to offer assistance on the design, goals, and objectives of the Palau International Coral Reef Research & Educational Center that will soon be constructed thanks in part to a grant from the Japanese government. Ornamental mariculture is just one way they hope to make the center financially self-sustaining.
As part of my duties with the Aquatic WildLife Co., I also spent 3 weeks last year in the Solomon islands educating the local collectors on some management concepts to helps sustain their sites and demonstrated to them how to culture some SPS corals
The aquarist own ability to share with others' invertebrates and reef fishes that they have cultured in their aquaria is becoming a bench mark of successful marine aquarium keeping.
The availability and diversity of cultured marine life in the trade today, compared to just a few years ago is astonishing! Maricultured live rock, propagated hard and soft corals, clams and the greatly expanded number of fish species beyond the once limited selection of anemone fish all helps reduce one of the pressures effecting the already stressed coral reefs of the worlds weather we feel we are impacting them or not.
Aquarist are also gaining an appreciation of cultured marine-life beyond the environmentally issues. Having been raised in an aquarium environment cultured marine-life are at home in one. Maricultured fish are pre-conditioned to the artificial diets normally offered by aquarist. They also experience much less stress in captivity than ones collected off the reefs, and as we know lower stress equates to less disease problem and an increase in their longevity in captive systems.
Aquarist also report a much higher successes with propagated corals then with ocean harvested ones. The theory being the propagated coral are better accustomed to the lighting conditions and flow rates provided by aquarist and grow or adapt "morph" according to the conditions.
Over the past several years our approach and attitude toward marine aquarium keeping has changed dramatically. While in the past we relied mainly on bacteria for filtration and focused our attention on the fish in the aquarium using bleached coral skeletons decoration. Now we more closely model a more natural reef ecosystem with reproducing live corals, healthy fish and unique invertebrates.
The reef aquarium has seen a lot of recent improvements towards replicating mother nature filtration methods from when the concept was first introduced. The transition from under gravel biological filters to wet/dry filtration was an understandable evolution for the marine aquarist and one easily excepted. In the early 80's the under the cabinet wet/dry contraptions with spinner bars and/or drip plates passing water over DLS material was introduced. Then Bio-balls, block, bale, and even plastic hair curlers replaced the lava rock, porcelain beads and DLS material.
Almost anything that would grow bacteria on it and brake up the water so O2 could be added and CO2 vented was used. As the reef keeping hobby continued to evolve, the US translation of the "Berlin" style of filtration enter the picture. The mentors of the reef hobby then started publishing articles telling aquarist to remove the their balls, from your wet/dry's. Perhaps this was just a male thing, but I found this required a lot of courage.
The US interpatation of the "Berlin" concept not only effected what happened under our tanks, but also effected what was happening inside the aquarium as well. Live rock was placed on egg-crate shelves so the aquarist could easily remove the detritus and help the protein skimmers maintain water quality. Later the modified US "Berlin" approach evolved and included the addition of a live sand substrate, paving the way for the Jaubert plenum technique.
Skimmers also continued to evolve with more efficient ones being introduced everyday. However, building a better mouse trap may not be the answer. While removing protein from a closed system is a very good approach, over skimming with the super efficient skimmers available today maybe taking out to much of the good with the bad.
This evolution also greatly expanded the bio-diveristy of marine-life that can be kept. Fish species, soft and hard corals and other invertebrate life forms that were once considered difficult or impossible to keep are now thriving in dedicated hobbyist aquaria.
During the years I spent in the ornamental mariculture business, I have had the opportunity to experiment with different types of systems. I have found there is more than one way to reach the same goal. The old saying "Don't fix what is not broken" applies to anyone who is happy with their present aquarium and the marine-life in side is doing fine. However, some methods seem to be easier than others to manage.
As we know the oceans inhabitants have evolved over millions of years in the most stable environment on earth creating an animal that has less tolerance to change than terrestrial animals. Aquatic creatures are dependent on stable water quality conditions, consistent photo period, water movement, habitat, and nutrition and are adversely effected by changes in these conditions.
This art of maintaining a successful marine aquarium is slowly evolving into a repeatable science and the key ingredient in most success stories is the aquarist ability to closely replicate what Mother Nature has so carefully composed.
This evolution towards a more natural reef aquarium has also intensified the spectrum of water quality perimeters we now need to be concerned about and the efficiency of our filtration methods. Water quality is a term that covers a lot of ground (or should I say water). Filtration, or the process that removes and/or converts toxins produced by the animals in the aquarium to less toxic forms is an important facet of maintaining water quality standards. Dissolved oxygen levels, lower levels of acceptable nutrients, a higher and more stable pH, alkalinity, Redox, calcium and other minor trace element levels, etc., have now became important factors.
As this list of acceptable water quality criteria increased, so has the number of gadgets designed to assist in controlling each perimeter. This influx of gadgetry, and the encroaching need for a minor in marine biology (not to mention the countless hours of care needed) to maintain a reef aquarium has catapulted this hobby to a level where the average person can no longer enjoy the esthetic beauty of a captive marine ecosystem of his/her own.
In an attempt to make aquarium keeping simpler, not more complex, the benefits of photosynthesis is now starting to gain attention among aquarists. Through the natural process of photosynthesis, pollutants within the aquarium are removed as the aquatic plants (algae) grows. The by-product of photosynthesis is life sustaining oxygen. This dual role of removing pollutants and producing oxygen makes photosynthesis a natural and efficient addition to the filtration process.
Photosynthesis occurs naturally in aquaria during the lighted photo period by macro and micro algae (plants) and photosynthetic animals (clams, corals, etc.). However, what happens when the lights go out and photosynthesis stops? The once plentiful oxygen levels are no longer being replenished and, even worse, the oxygen producers now become competitors by striping the oxygen from the water and releasing carbon dioxide. The dark tank becomes a nightmare for the inhabitants. As the oxygen levels are lowered and the carbon dioxide increases, the pH is also effected changing the once ideal conditions and causing stress to the animals. This daily roller coaster ride (fluctuation) is not normal in nature.
However, if the photosynthesis process was able to continue 24 hours a day somewhere within the water column (RDP) it would duplicate the nocturnal influx of high oxygenated, low nutrient water from the open ocean. When the lights go out over the aquarium, the lights should come on over a garden of macro- algae (out of sight to the aquarist) in the RDP filter box . This "garden" of specially selected species of algae would continue to remove pollutants, replenish the oxygen, and greatly contribute to the stability of a closed system.
The RDP filter box should be designed for maximum efficiency and low maintenance. The garden of algae is grown on a plastic screen that can be easily removed for periodic harvesting. Removing the screen and scraping the mature algae off with a plastic automobile windshield ice scraper every 10 days or so will insure that the most efficient new growth is always in development.
The algae that remains attached after harvesting will rapidly regenerate new growth. After harvesting, the screen can be rinsed under freshwater to remove any unattached algae. This freshwater rinse will also kill any herbivorous invertebrates (i.e. amphipods) that may have started to colonize within the garden. The entire harvesting and rinse process takes only minutes once every ten days, but the benefits of RDP are well worth it.
Protein skimming has also been referred to as a natural method of water purification. The much sited example of foam washing up on a beach during a windy day serves as nature's way of removing proteins and other organic compounds. This purification process is replicated by aquarists within a cylinder where water and small air bubbles mix and foam is produced. Amino acids, proteins, etc. are trapped in the foam and deposited in a collection cup. While the physical removal of certain compounds from the aquarium is beneficial, too much of a good thing in this case can also have a negative effect.
Protein skimming was introduced to the aquarium hobby in the early 70's, but the over use of it has been around equally as long. Following the recommend "rule of thumb" of passing 100% of the aquarium water volume through the skimmer every 45 minutes on a continual basis is an extreme exaggeration from the example of occasional foam on the beach created by nature.
Over skimming can remove beneficial plankton (the major component in the food chain) faster than it can reproduce. It can also remove desired trace elements (especially iodine), vitamins, food, etc. which ultimately must be replenished. The replenishment process of required trace elements is either a labor intensive job which requires some degree of expertise or an expensive process that requires a number of space age gadgets.
If the goal is to make aquarium keeping simpler, then a reduction in skimming and the addition of photosynthesis may be a better approach. Moderate foam fractionating (key word is moderate) in combination with RDP will allow the positive effects of each to more than balance out any negatives. .
In an attempt to more closely duplicate the natural aquatic ecosystem (remember this is the key ingredient in most success stories), live rock and live sand is also part of the RDP concept. The addition of a proper substrate bottom, which was not part of the original US interpatation of the "Berlin" concept contributes to the filtration process and helps support the natural levels of calcium, strontium, and other beneficial trace elements found in sea water. Just think how much sand is on the bottom of the ocean and the amount of life it contains. By not including this in your aquaria, you are missing a very large portion of the biome.
Healthy live sand contains microorganisms growing on and in it. The use of this natural substrate also provides habitat for many fish and invertebrate species that were not able to be kept in the past, but now increases your selection of ornamental Aquatic WildLife which can be added.
Live Rock (the backbone of coral reefs) has a variety of algae and microorganisms growing on and in it. Live rock is much like the live sand in that also plays a key role in the filtration process and provides habitat. The addition of live rock, however, does not have to be limited to "reef" aquaria. Corals, plants, spiral gilled tube worms, and other life forms found on "decorator" live rock that would become expensive forage for the fish species normally kept in "fish only" tanks do not have to be added.
Live rocks encrusted with rainbow colored coralline algae can, however, replace the bleached coral skeletons normally used as aquascape with these fish species. This coralline rock will provide the same esthetic value as bleached coral and at the same time contribute nitrifying and denitrifying bacteria and other microorganisms.
Note the word Healthy used to describe the live rock and live sand. When "live" rock and "live" sand is packed and shipped from some exotic South Pacific island extended shipping times are required before it arrives in the USA. This time out-of-water (or box time) takes its toll on most of the organisms that live on and in the rock and sand. The once "healthy" live rock and live sand arrives essentially died.
Cultured live rock and sand purchased from mariculture facilities located within the continental US or harvested rock and sand that has been maintained in an ecosystem (closer to the market) for a period of time long enough to allow it to recover from the stress of shipping, offers a number of advantages. If ocean fresh (read live) rock and sand is used to establish an aquaria it will not have to go through the "normal" cycle period before all the animals you desire can be added. A properly aquascaped RDP concept aquarium can be setup from an empty tank to a fully loaded system in less than 48 hours.
Replicating natural light is also a critical key element to the long term survival and well being of corals and other invertebrates especially those that are photosynthetic (use light as food). Selecting the proper light intensity (watts), Kelvin temperature, (color) and style of bulbs (Power compact florescent, metal halide, VHO & HO florescent, etc. or even a combination of these) best suited for the type of aquatic biome you want to duplicate can be a time consuming and confusing task.
There is as many opinions as to what type of artificial light source is correct as there are styles of bulbs. Since this article is on RDP and not an in-depth article on lighting, I will leave choice of lighting up to the individual who sets up the aquarium.
However, it has been suggested that replicating the natural lunar phases may induces sexual reproduction and a more natural behavior in most aquatic life, including stony corals.
This simulation includes the time the lunar light comes on, how long it stays on, the increase and decrease in intensity as the moon goes through its cycle from new to full, etc. It may also be beneficial to the behavior and well being of some aquatic life to increase and decrease the daylight Photo period and intensity in a more realistic simulation of natural lighting variations, including sunrise, sunset, high noon, and length of daylight (winter through summer) etc. It is for these reasons that the RDP concept begin outlined suggests that a preprogrammed micro-processor that automatically controls all of these functions be part of the integrated system.
Water movement is an meaningful part of the aquatic world, effecting respiration, feeding, growth and reproduction of corals, fish, calms, plants and other aquatic life. The RDP concept also duplicates the three main types of natural water movement, wave action, turbulence and laminar flow.
The natural back and forth action caused by waves normally missing in aquariums does more than add motion and interest. In nature, it plays a key role exposing more of the surface area of the flexible corals to sunlight, increasing feeding efficiency and the exchange of metabolites and gases within the water. Waves also disturb and mix surface layers and create ripples. These ripples magnify the light forming "glitter lines" or bands of light brighter than the normal ambient light. This moderate strobe effect adds the appearance of motion, depth and interest to the aquascape and at the same time provides the beneficial effects of pulsed energy to the animals.
Turbulence is caused when the natural wave action (surge) meets the more Laminar or constant one direction flow produced from the spray bar. Replicating the three main types of water movement found on a coral reef provides different biomes or aquatic zones that many organisms evolved in.
Meeting the Nutritional requirements of the variety of captive animals can be a full time job. Herbivores, carnivores, omnivores, planktivoures, and detritivores are classifications of Aquatic WildLife based on what they eat. However, they all have one thing in common. In nature they all forage, graze or filter feed continuously. The easiest way to provide the proper nutrition on a continues basis is to replicate what nature does.
By introducing the smaller life forms (i.e. copepods, mysid shrimp, etc.) and providing natural habitat (live rock and sand) for these living vitamin capsules you provide natural forage for the carnivores and omnivores that they can seek out and eat. However, being efficient hunters they can deplete the natural population in an enclosed system rather quickly. In the RDP concept aquaria a refuge area is built into the main tank design as a safe harbor for delicate organisms to live and reproduce away from predators. It shares the same water as the main tank, allowing some of the organisms to enter the main tank as natural live food.
The larval stages of these copepods, mysid shrimp, and other microorganisms that live and reproduce in the refugia enter the main aquaria as plankton, thus feeding the filter feeders and planktivoures. The herbivores and detritiovrs are primarily introduced to an aquaria as natural maintenance engineers and will feed themselves. The incorporation of a properly designed refugia can greatly reduces the need to manually feed the aquarium.
The refugia also aids in the filtration process, replicating the lagoons and estuaries in nature. The slower moving water (in comparison to the rest of the aquarium) allows solids to settle out (natural mechanical filtration) so bacteria and detritiovrs can break this down. The refugia can also serve as habitat for ornamental organisms (i.e. coral banded shrimp, etc.) that might become food for predators kept in the main aquarium.
This refuge is incorporated in such a manner so individuals who wish can easily view the inhabitants through one end of the aquarium and/or through the window from the front of the aquarium. This design does not distract from the esthetic design of the over all aquaria and puts the refugia out where it can be enjoyed.
Designed with the non-aquarist in mind, the RDP system allows the average person to enjoy the educational benefits and soothing beauty of the aquatic world within their own home or work environment.
Televisions, stereos, computers, etc. are no longer purchased as individual components to be pieced together by the average consumer, but rather are available as a complete package that was designed by professionals to perform successfully and as simply as possible. So, why not aquariums? The RDP concept is a well designed, integrated aquarium system that models natures ecosystem.