Timo McIntosh Arts

The Aquarium Keeper's Notebook

The ancient Chinese found that keeping fish and cultivating their beauty was not only a prideful craft, it was a relaxing and careful meditation. To many beginners, the a fish tank is no more than a place where fish live, food goes in every day, and water gets changed every two weeks. While this is quite enough for some fish and some people, it represents only a small part of the ecosystem that can develop and the relationship that be forged between the care-taker and aquarium.

Keeping fish can become more than just a fixation on taking care of an environment. Aquariums can flow into forms of art, spirituality, and a connection to the natural world. They are built on their owner's whims, but they also form unique personality down to the individual fish and plants that inhabit them. Aquariums are subtly in balance and can flourish or ruin without a sight or sign to the outsider.

Fish are simple. They swim. They eat. They breathe and they breed. That's about all they do individually, but when pieced together into an environment, they can become part of a living breathing tapestry of movement, color and life. Fish provide us with reminders of who we were and what we are beneath our chaotic surroundings. Fish brought inside the home not only provide a sense of control and closeness to the natural world but they tie the aquarist to the entropic and cyclic processes that govern everything. Aquarium fish live and die despite their keeper's objectives, but also depend fully on the environment for their quality of life. Aquariums are isolated and contained within artificial worlds but they give the aquarist an ideal and simple bridge into the harmonic beauty only nature can bring.

All too often, fish keepers content themselves with a baron fish bowl and a couple of murky goldfish, thinking that any more will place unwanted demands on their lives. While somewhat true, the investment in a larger aquarium and acquisition of some simple knowledge can alter the health and mood of an entire household. Keeping nearly indestructible goldfish trains the aquarist in the ritual feeding and cleaning necessary for all pet keeping, but doesn't develop the sense of subtle care needed to maintain a healthy and vibrant aquarium environment.

This subtle care takes into account environmental factors that are often overlooked even in human dwellings. Water quality and chemistry, lighting, oxygen demand and CO2 availability, communal stress and temperature all play large parts in bringing harmony to the aquarists environment.

Water Chemistry

The nitrogen cycle in fish tanks is the most important aspect of water conditioning, but is also the easiest to remedy. Even goldfishists understand that fish live and breathe in the same water where their food and waste end up. This knowledge prompts the weekly to monthly water changes that all aquarists partake in. What often is overlooked though, is what the replacement water is like when that change occurs. PH, hardness, and chlorine come up as the second most scrutinized class of conditions to check for, and for good reason. Unlike nitrogen compounds which will disrupt or destroy an environment within days, a PH or hardness stress will cripple fish and plants over the course of weeks and months.

The environments aquarium organisms are used in the wild are very clean, ph balanced, and consistent from week to week. Although this is not true for all species that might be kept, these conditions are optimal and necessary for most tropical fish and plants. The majority of aquarium fish and plants are from the Amazon, Asian or African rainforest regions. Rainforests receive a lot of rain, hence the name, and by their structure are fantastic water filters.

Some fish and plants live in hard water and non-neutral water conditions though, and it is important to know which ones do and which ones don't. For this knowledge the internet is a fantastic resource. Often, pet store guides and employees don't know the origin of the fish, and only can guess at the appropriate water conditions, which can vary in the wild from one mile to the next. The internet can provide the geological and natural history of an entire river basin, not just the tolerated water conditions of a family of fish. Knowing the origins to the river will let the aquarist decide with facts what water type fish and plants come from, and how those conditions change over time.

Most aquarium inhabitants sold at pet stores tolerate water chemistry that is unlike their home environment, but it is important to know this fact because tolerant fish do not necessarily mean successful fish. Besides forgetful fish keepers, stress from tolerated but non-optimal water conditions is the largest long term problem for aquariums. Fish and plants deteriorate and become sick because of stress, not contact contracted illness like in humans. Fish in fact live with a layer of diseases and germs on their scales and skins their whole lives, and it is only when a fish becomes chronically stressed that those germs will do their dirty work. Therefore, it is important to consider whether water conditions are simply tolerable to the aquarium inhabitants, or whether the water conditions are ideal for the fish and plants in the tank.

Air Flow

Another factor to how well water is suited for fish and plants, is how much oxygen and carbon dioxide are in it at any given time. As most people know animals breath oxygen and give out carbon dioxide, and plants do the opposite. Many people don't realize, though, that these are not a counterbalanced cycles. There is much more oxygen in the air than carbon dioxide with nonliving systems contributing to and reducing both. Also, too much carbon dioxide in a system becomes toxic to animals. Second, oxygen and carbon dioxide in water do not behave the same way as in the air. Carbon dioxide is not very soluble in water. This is why carbonated beverages bubble when they are released from pressure. Oxygen on the other hand is soluble in water and concentrations are primarily dependant on surface area. Maintaining the appropriate levels of both gases may not always be vital, but they shouldn't be overlooked.

Like their land counterparts, aquarium plants and animals have varying oxygen and carbon dioxide needs. Some fish, like goldfish can extract enough oxygen to breathe from very oxygen poor water, unlike a trout who will suffocate in all but the highest oxygenated waters. There are also labyrinth fish, like the Beta and Gourami, which don't extract any oxygen from the water at all, and take in air from the water's surface to mix in with the water before passing it through their gills. There are many methods available to the aquarist for the different oxygen needs of fish, but there are very few if any products available for plant carbon dioxide needs. It is important to know what is how an aquarium is out of balance before searching for solutions though.

Bubblers, waterfalls, and pumps are the most common ways to oxygenate an aquarium, but not necessarily the best for the environment. Plants need carbon dioxide as much as fish need oxygen, so it is crucial to find a balanced approach to circulating and oxygenating water. While waterfalls and bubblers can provide more than enough oxygen to fish, they also remove the carbon dioxide that plants need. There is therefore a subtle balance between fish and plants that should be sought. Usually, oxygen demand is overestimated and results in oxygen loving algae and sick plants. Sometimes tanks will be over crowded with fish providing great plant habitat, but causing the fish to gasp for air constantly. Usually a well planted aquarium with an appropriate number of fish, supplemented by a small mechanical circulatory system is the best approach at finding this balance.

Keeping both plants and fish in an aquarium is ideal for many reasons. Plants function as oxygen providers, nitrogen fixers, ph stabilizers, hardness reducers, pleasing and natural habitat producers, and hiding places for fish. The fish in turn provide the plants with nutrients, carbon dioxide and in some cases cleaning.

Lighting and nutrient Cycles

To keep both plants and fish an aquarist must look closely at the lighting in the environment. First and foremost, plants need plenty of light. Even shade loving plants in the aquarium need more light than most aquarists think. At a minimum, two florescent bulbs should be over the tank. Adequate full spectrum lighting will aid in keeping all the environmental cycles running smoothly and efficiently. It will also allow the tank to be seen in its beauty during the day, when ambient light shines on the aquarium.

Good lighting also promotes nutrient usage. With a well rounded and complete plant habitat in an aquarium, nutrients, which are fish pollutants, will be used quickly and completely. If they aren't, algae will begin to grow. Not all algaes are created the same, though. Blue/green algae, although unsightly can be an aquarist's coalmine canary when a tanks swings out of balance. Blue/green algae is a sign that the aquarium environment is out of balance in up to three ways; nitrogen imbalance, oxygen imbalance, and over lighting.

First, blue/green algae will only grow in the presence of nitrogen compounds. If you have plants and blue/green algae starts to grow, it means that the plants combined with the tank's brown algae aren't coping with fish waste completely. Brown algae converts ammonia (highly toxic) to nitrate (less toxic) and then to nitrite (slightly toxic). The aquarium plants will then use the nitrites and some nitrates as nutrients to grow.

Unfortunately, the nutrient path doesn't end there. Plants need more than just nitrogen compounds. Plants also need minerals, often called micronutrients, to metabolize the nitrogen. When it comes to nitrogen mobilization, care must be taken, because there will always be an excess of nitrogen over a period of time no matter how efficient the plants become. Plants are incapable of utilizing all the nitrogen, so when blue/green algae grows, a water change is over due and it is time to add some micronutrients for the plants.

Second, blue/green algae consumes oxygen, unlike plants. This can be dangerous to fish if too much algae is left in the tank. The oxygen demand of the water goes up with ever bit of algae that is in the water, so fish will slowly suffocate if the oxygen demand becomes too high. There is also a balance here, because high oxygen concentrations will make the fish breath easy, but also promote algae growth. So in the presence of high oxygen levels and nitrogen, an aquarium might see a blue/green algae bloom in only a few days.

Finally, too much light can cause an environment to grow out of control. Aquariums in full sunlight often turn green with algae and plant material. The light causes plants to grow fast, utilizing weeks of micronutrients in days. This in turn causes the plants to fail to utilize nitrogen, which in turn stops growth and leads to leaf die off. Once the plants start decomposing they start releasing nitrogen back into the water, which provides the perfect conditions for blue/green algae; light, nitrogen and oxygen.

Daily and Seasonal Variations

Also often overlooked, is daily light cycles and seasonal changes. Although fish don't sleep, they take their behavioral cues from the time of day and season. Unbenonced to many, long days and slightly higher than normal temperatures can trick fish into thinking they live in perpetual spring and summer time. Although in some fish this is a low stress time, due to a bounty of food and fresh clean water, most fish equate warmth and light to breeding, and can stress themselves with continual breeding displays and coloration.

Temperature or daylight variations, or lack thereof can also lead many fish into irregular eating habits and activity cycles. This can be disastrous to nocturnal or diurnal species, who may only eat or rest during certain times of the day. While in nature a river may only vary in temperature over the course of several months by a few degrees due to its large heat capacity and mass, an aquarium may vary wildly on a daily bases due to fluctuations in the ambient air temperature. Conversely the use of well insulated aquariums and efficient heater, may prevent the water temperature from changing at all. Unfortunately, there is no catch all way to deal with this without spending a fortune on computer controlled heaters, but an aquarists shouldn't overlook temperature or light intervals when considering why a fish are overly active, or unusually dormant.

Schooling

Fish are the only other creatures, besides humans, who partake in schooling, but they aren't as civilized as schools denote. No fish likes being around other fish. Other fish are competitors in every aspect of life, so schooling is only a last resort in the presence of danger.

Pet store clerks and generic pet fish books frequently recommend that schooling fish like tetras and rainbows be kept in groups of at least 5-7, because they are schooling fish. This is poor advice. In the wild schooling fish like tetras are found in groups of hundreds and thousands of fish, and it is only in these very large groups that their schooling behavior will suit them.

In small groups of less than 50, besides breading pairs or harems, most fish will revert to individual competition. This competition adds a great deal of stress to the fish, and even more, may result in fin nipping and aggressive behavior among otherwise peaceful fish. It is a wondrous sight to see a small group of fish in an aquarium school when startled, but it is not the norm. Keeping enough fish to school will almost always result in the continual replacement of individual fish who succumb to the stress of being around so many other fish. Although in the wild an individual's death in a school is routine, in an aquarium it can be costly.

Crowding and Fish Choice

In general, a well planted tank may have up to an inch of fish per two gallons of water if there are many different species of similar size, and a great variety of habitat. Otherwise, half as many fish usually provides a much more successful environment, and a quarter as many fish for similar species.

More important than the size of the fish, though, is the area of their territory, which all fish have. With schooling fish, the size of the school as a group will roughly give you an idea of how much room each fish will need. By multiplying the size of the school by how many fish are in the school, the result will have the total area all the fish in the school will need. For example, a school of five fish in 6 inches of space will require 30 inches of free space when the school is in individual mode.

With aggressive fish like African cichlids, a minute watching each fish will provide more than enough insight into how much room they like. Also with aggressive fish, "bomb shelters" are vastly important. A bomb shelter is a place where the fish can hide where no other fish in the tank can get at it. Aggressive cichlids and other "community" species can be mixed in some cases, despite the protests of pet store advisors, but size is the most important aspect of this mixing, as it is with any and all fish. Smaller slower cousins are punching bags, and a tiny fish is a food fish if the mouth fits.

Overall any aquarium community or species should be closely compared to the environment that can be provided to it. The aquarists water changing discipline, ph , hardness, and tank size and inhabitants should all be judged with the utmost importance when deciding on the fish composition of a tank.

Good aquarium keeping

Aquariums are more than just pretty and fun hobby props. They are the result of an art form that has been practiced for hundreds of years, and more importantly, they are a symbol of the natural world and everything that is alive in it. A dirty, disease ridden and ugly tank can depress any inhabitant or guest, but conversely a clean and lively aquarium in the home can provide people with a bastion of sanity, beauty and tranquility as well as promote good health and happiness.