Is there a Need for a Successful System?

By Sam Gamble

The aquarium industry is again in a state of flux. Not so long ago we were content to use the buzz words; filtration and the nitrogen cycle. Simple. Our vocabulary and knowledge is still expanding. Our new buzz words are; natural system, Berlin method, Jaubert method, Natural Nitrate Reduction, Sand Bed System, nitrification, carbonization, and benthic ecology. Or one of my favorites, "biogeochemical pathways". Is it getting simpler, or more complex? Let's hope it's both.

Hopefully this paradox will come about with the materialization of an aquarium system that maintains itself. Doing it without much more than natural components arranged purposely. Then the necessity for reductionist reasoning can evolve as interest dictates. For the future of aquariums, where do we go from here?

In the last five or so years, natural systems have achieved greater success, with greater diversity than ever before. This has been the result of more application of ecological principles. These concepts have stood in the wings admittedly too long. Now we are more able to easily and successfully maintain some of the oceans' most delicate and beautiful creatures. We are beginning to realize the role of energy is more important than just light and heat. We are also beginning to learn the importance of synchronizing radiant energy and it's myriad of transformations between microbes . Energy "cycling". Energy "shared".

The nitrogen cycle has been the important emphasis for our closed systems over many years. However, carbon is the most demandingly critical element for life. Without carbon being present, it is unacceptable to use the words organic or biological. We must not forget that nitrogen and carbon energy cycles are tightly and concomitantly related by the pathways they follow.

For some time we have utilized ways to reduce toxic wastes containing nitrogen. Particularly ammonia and nitrite because of their toxicity at relatively low concentrations. Filters and filtering systems were born. Thus we easily accepted a concept that was neatly explained by the nitrogen cycle. At first nitrate was considered the end of the road and "okay". This was because it wasn't thought to be directly toxic unless it accumulated in very high concentrations. It was not until less tolerant species were desired that methods to remove nitrate were sought. Keeping cnidarians was a key to the evolution of our focus beyond just the overemphasized nitrogen cycle.

And now, recently another part of the dogma has been challenged. In the study, Comparative Analysis of Nitrifying Bacteria Associated with Freshwater and Marine Aquaria" (published in the August '96 Journal of Applied and Environmental Microbiology) by Timothy Hovanec, under the direction of Dr. Edward F. DeLong, it was revealed that in freshwater aquaria, Nitrosomonas and Nitrobacter bacteria DO NOT drive the nitrification process. Also in the study it was revealed that in saltwater aquaria, Nitrosomonas is present, whereas Nitrobacter is NOT .

Prior to these findings, Nitrosomonas and Nitrobacter bacteria were always accepted as the bacterial groups responsible for nitrification in aquatic environments.

The fate of nitrogen in the nitrate molecule is only a small part of the cycle, and it is associated with carbon by the needs of the microbes. The carbon and nitrogen cycles are of fundamental importance and inextricably linked to marine microbial production, mineralization, and sedimentation processes. Importantly, those macromolecules mediating biochemical transformations (protein - enzymes) and physiological regulatory, or genetic controls (hormones, growth regulators, DNA,RNA), show a common reliance on specific ratios and configurations of carbon and nitrogen. It is then not surprising that nitrogen and carbon limitations of microbial metabolic activity and growth, have important consequences for production and mineralization of organic matter in a marine environment.

Given the close coupling of carbon and nitrogen cycling in marine production and mineralization processes, it seems intuitively obvious that our alteration of and interference with, natural cycling of these elements has and will continue to produce significant impact on marine fertility and resultant water quality. The nitrogen and carbonization cycles facilitate decomposition of organic wastes allowing certain organisms to out compete others.

The energy transformations are step wise processes, controlled by the cell and the environment it produces. In many instances an unbalanced aquarium or an improper environment, upsets the natural balances of energy cycling and produces the need for external filtration to remove elements not used. The desired pattern of transformations has been changed. Synergistic equilibrium has been partially destroyed or damaged.

It is very important to understand the energy cycling concept to focus on what nitrate means, as a nutrient, by what physical pathway it must follow to be used by the living cell (microbial mediator). Also, it is important to understand that it is metabolism (chemical transformations) adaptively breaking down or synthesizing compounds, that ultimately causes pollutants to stay at proper levels. It all adds to the scope of the picture for benthic ecology and "biogeochemical pathways", that our new approaches rely on.

The best system and maintenance practices control energy sources and products. The first requirement being to satisfy the needs of the organisms chosen for the confined environment of the aquarium. Second, the system must maintain chemical energy in a way that allows balance. Even the most efficient filtration system can be over burdened by the influx of too many sources of organic compounds for the system to metabolize. This creates imbalance. Monitoring water quality will help indicate a increasing flux of nutrients and aid correction.

Life has a balance in every event from microscopic to macroscopic. We observe balance as conducive to our way of life sustaining events of things or creatures we wish to preserve. If you are trying to maintain an aquarium, you must consider the main culture you wish to preserve and then realize the countless microscopic events must happen to maintain the macro cultures. The best way to understand the system is to understand the single cell and what it needs to promote its equilibrium. Not just the machinery, not just the additives.

Again we come around to the topic of cells and energy. The initial source of energy in living organisms comes from the sun. The energy arrives by units of light and is trapped by the pigment chlorophyll. Chlorophyll is present in the cells of green plants, and accumulates as chemical energy within the different foodstuffs. Without the sun, there would be no life on this planet.

Obtaining and using energy other than radiant (light) requires energy transformations locked within chemical or potential energy of foodstuffs by different covalent bonds between the atoms of a molecule. Inside the living cell this enormous amount of energy is not released suddenly as in the combustion (oxidation) in a flame. Instead it proceeds in a step wise and controlled manner, requiring and using dozens of oxidative enzymes that finally convert the fuel into CO2 and H2O, liberating energy.

The creation of the "optimal ecological environment" would allow reproduction of many of nature's secrets for obtaining and using energy. Most importantly is the successful use of energy, which includes the important pathways for cycling. This becomes energy used and energy shared. We have made some advancements recently. But, until we can accurately and consistently cycle all the compounds and elements we put into our aquariums to result in useful energy, we have to keep searching. Biological filtration, natural systems, and sand bed systems have been important mile stones on the road to better aquarium science; the future. There is still a need for a successful system.

Questions &\or comments Sam Gamble 102170.3150@compuserve.com