Biological Filtration and Sea Life Acclimation

When adding life to an established aquarium there is one main rule that all aquarists must follow. . . take it slow.

Everything about adding to a tank must be slow. An aquarist should add a small number of fish at a time (I add one at a time to my ten gallon tank. I also wait at least three days between fish additions). This is because your tank needs to catch up to your recent additions.

Every established aquarium, saltwater and freshwater alike, has a biological filter that builds up. There is a common misconception that a biological filter is based on the tank size, its not. Your biological filter is established based on the bio load (fish waste) in the tank.

When a fish enters an aquarium it immediately begins to add to the tank's bio load. Fish waste begins as ammonia. Over time bacteria called Nitrosomonas will develop that consume ammonia. After consumption, the bacteria's excretes a waste product called nitrite. Although nitrite is less toxic than ammonia it is still very dangerous for fish. Once the nitrite joins the aquarium's water chemistry, another bacteria begins to develop. Nitrobacter consumes nitrite and leaves a waste product called nitrate. Nitrate is virtually harmless to fish (unless you get above 40ppm in nitrates, at that level anything is dangerous), in fact nitrate is a great food source for plant life.

The biological filter establishes itself through consumption. If an aquarist adds a formula of concentrated bacteria to their tank (i.e. Bio Spira) the water will become cloudy because of a bacterial bloom, but eventually clears up. The explanation for this also explains the size of the biological filter. Like all things, bacteria need a food source to survive. When bacteria enter the tank they begin to eat all of the ammonia and nitrite available. Those that are unable to eat any ammonia or nitrites will die thusly establishing the size of the biological filter. Since the biological filter is very specific to the current tank arrangement, adding fish must be done slowly as the filter will need develop more bacteria to keep up with the bio load.

There is a certain strategy many aquarists employ to prepare their fish for the aquarium as well. A fish may be in their tank at the local fish store for several days and are most likely comfortable there. When you bring them home you have changed quite a bit for them. Their habitat, the water chemistry, the temperature and probably the food, so take it slow. The drip acclimation method works very well for most sea life.

Take a plastic container of decent depth and fill it with the water from the bag the fish came in (allow the fish to enter the container as well). Then empty out enough water so the container is only half full (allow a little bit of extra water if it is necessary to fully submerge your fish). Place the container close to your fish tank, but lower than the top of the tank. Take some spare air hose for an air pump and fully submerge both ends into the aquarium, make sure both ends of the hose are facing up. Maneuver the hose so that it is filled with water and you have worked out all of the air. Then hold one end of the hose in the tank as you bring the other to the plastic container. Once you point the end into the plastic container water will start to flow out due to a gravity siphon you just started. Use a binding clip or anything to constrict water flow through the hose so that you have a drip rather than a steady flow of water. Allow the drip to continue for the next 15 - 30 minutes (you be the judge, longer is better).

The drip method offers quite a few benefits. First is that it very slowly introduces the tanks water chemistry to the sea life as it combines the new water with the old water. The drip will slowly acclimate your new tank member to water hardness, temperature, and pH. Also, the physics of the drip work the same as the "water-fall effect" in which oxygen is introduced to the plastic container via the downward motion of the water ensuring enough oxygen to the fish/plant/invert being acclimated.

After 15 - 30 minutes, net the fish/invert or pick up the plant and place them into their new home. Do NOT simply pour them in, you do not want the contaminated water from the plastic container entering your fish tank! Always monitor your new members closely to check for signs of distress from water chemistry or other species.

Source:

Personal Experience

10th Grade Biology