An outside filter is a watertight box suspended outside and alongside of the aquarium. Usually it is made of plastic or glass. The top of the filter is level with the rim of the tank. The filter itself is divided vertically into two unequal compartments by a partition, the lower one-quarter of which is perforated or slotted. The filtering material is placed in the larger compartment. A small tube siphons water from the tank onto the filter material. It sinks through the filter material and runs through the perforations in the partition into the next compartment. The passage of the water through the filter material has cleansed it. The clean water is returned by means of an air-lift tube, which is operated by the pump.

As the intake stem bringing water into the filter is a siphon, it maintains the water in the filter at the same level as the water in the tank. Therefore, the water cannot over-flow. The action is continuous. If the siphoning action is stopped, the return stem - which returns the clear water to the tank - would empty the filter. As the amount of water the filter is usually small compared to the volume of the tank, no harm is done, that is, the tank will not overflow.

For an outside filter to operate efficiently, the water level of the aquarium should be quite high, about one inch from the top. The siphon tube is placed upside down in the aquarium to empty it of air. Still held under water, it is righted, and a finger placed over the shorter open end. Holding this tightly closed, the tube is lifted far enough out of the water so that the short end of the stem can be put into the larger filter compartment, and the longer end remaining submerged in the tank. Only now should your finger be removed from the end. The flow should start and continue until the water level in the filter and the tank is the same.

There are several self-starting stems available today. To start them, hold your finger over the opening in the short end and slowly lower the stem into position. Syringe-type starter balls are also available. This type and the automatic or self-starting stems do offer a good deal of convenience.

What is the Best Location for a Tropical Fish Aquarium Pump?

It is usually advisable to have the pump at a higher level than the tank. This will prevent any possibility of a siphoning action draining the water from the tank back into the pump. Pump platforms are available for pump placement. These are small plastic or metal shelves designed to hold the pump while hanging on the back of a tank.

If it is desirable to place the pump on the floor, or on any level below the level of the tank, there are several precautions to be observed: Backflow seldom starts while the pump is in operation; it is when the pump is not operating that the greatest danger occurs. Backflow may be started by several actions.

(1) The tendency of water to rise in a narrow tube is known as capillary action. If the water in the tank is very close to the top, it is possible for water to rise in the air tube by capillary action to a point where it starts a downward flow and a siphoning action occurs.

(2) The cooling down of a warm pump can cause the air inside to contract and draw the water down.

(3) Over- oiling the pump can cause excess oil to enter the lines. Air pressure will keep the oil clinging to the inside walls of the vertical tubing, but with the air pressure removed; the oil starts to run back. As it collects in droplets, a vacuum is created behind it strong enough to start a siphoning action.

In order to prevent this, keep a small surgical type “C” clamp handy. When, for any reason, the pump is shut off, clamp shut the line leading to the pump. Also shut all air valves tightly. Whenever oil or moisture is seen in a tube, discard that piece of tubing. It is also a good idea to clean the pump when excess oil appears in the line.

How Does an Aquarium Thermostat Operate?

Aquarium thermostats all utilize the same principle with variations only in quality, construction and design. The basic principle behind a thermostat is that metal, when heated, expands; and that different metals expand at different rates. Two flat strips of different metals are bonded together. When heated, the metals’ unequal coefficients of expansion result in a bending of the strip. One end of this bimetallic strip is fastened rigidly in place and one end of the circuit is fastened to it. The other end is free and rests against a screw in a metal plate to which the other end of the circuit is attached.

As the bimetallic strip warms up, it curls away from the screw against which it is resting, thus breaking the contact and the circuit: With the circuit broken, the heater stops heating. As the water surrounding the tube cools, the drop in temperature is transmitted to the bimetallic strip, which - being cooled - straightens out again and re-establishes contact and turns on the heater.

The screw against which the lower end of the thermostat rests is threaded and may be turned to increase or decrease the distance between the points of contact. This varies the extent to which the metal must bend in order to make or break the contact. The metal always expands and contracts the same distance at given temperatures. Once the proper spacing has been reached for the desired temperature setting, it is only necessary to leave the screw setting alone.

The closer the contact points, the more heat is required before the circuit opens. The farther apart, the colder it must get before the contacts come together. In order to raise the aquarium temperature the adjustment screw is turned so as to bring the points closer together, and to lower the temperature, the points should be separated.

All adjustments should be made gradually and checked frequently with a thermometer to avoid sudden extreme changes of temperature. Usually a quarter turn is sufficient to raise the temperature 3° to 5°.

Some of the more elaborate thermostats have adjustment knobs projecting above the top. They are connected Icy means of threads or movable plates to the contact points. However, the principle remains the same: varying the distance between the contact points determines the temperature at which the circuit will open and close.

Some aquarium thermostats are sensitive to as little as 1 1°. However, such extreme sensitivity is not necessary; usually + 3° is adequate for aquarium use. Some cheap thermostats are even less sensitive and less satisfactory.

Most thermostats arc made to operate at an adjustment between 60° and 110°. Should you try to set the thermostat temperature lower than 60′, the adjusting screw would be at too great a distance from the bimetallic strip, and contact could not be established. Conversely, should you attempt to set the thermostat for more than 110° the screw would be pressed so tightly against the thermostat that the strip could not curl far enough away ever to break contact and stop the flow of electricity.

Aquarium Light Tips

Fish don’t need so much light as the plants do. A dim light is sufficient for fishes - usually just enough for them to see food. Very few fishes will eat in the dark. An exception is the Catfish; Catfishes, as a group, are largely nocturnal in their activities.

When no light reaches the fish tank, a great change comes over the fishes. Switch a light on suddenly after a protracted period of darkness and you will find most fishes in your tank are motionless. With few exceptions you will find that their color has faded. Such fishes have the brilliant red-and-green Neon fade to a white and light pink. Many fishes, you will notice, are lying on the bottom of the aquarium.

It should also be remembered that it takes some time for most fishes to adjust to a sudden light. If they are disturbed before their eyes have adjusted, they dash blindly about, even leaping out of the water. It is useless to feed them at this time, because they cannot see the food.

On the other hand, constant light seems to do no harm. Fishes in aquaria under constant light appear to live just as well as those that have alternate periods of darkness and light. The breeding cycle of many animals is controlled by the increasing and decreasing of the number of daylight hours as the seasons change. But very little work has been done with fishes in this field. What little has been done shows that light is a definite factor in the breeding of some, but not all, fishes.

Recently published experiments conducted with the young of certain marine fishes indicate that the fish will grow more vigorously when given a period of darkness in which to rest. How this affects the total longevity of the fish is not known.

There is no hard-and-fast rule governing light for the aquarium plants. It varies with the type of light, intensity of light, depth of water, kind of plant, the distance the light is from the water surface, and the amount of daylight that reaches the tank. Usually, if the fish tank is kept in a shaded area of a room, you should provide some artificial light in order to supply what the plants need. Lighting from a reflector which can be regulated is covered later.

Should I Buy Small or Big Aquarium Tank?

A small fish tank is not recommended because it is limited in its capacity and can very easily be overstocked. Overcrowding, like any other excess, leads to trouble. A conscientious dealer will warn about overcrowding when you are buying too many fishes. Get his advice by telling him the size of your tank. A 5 gallon aquarium is only a couple of dollars less than a 10-gallon aquarium. In fact the cost of the equipment will run about the same to outfit a 5-gallon aquarium as it would for a 10-gallon aquarium.

The reason for this is that most of the equipment you will need for the 5-gallon aquarium is the Hume used for the 10-gallon aquarium. Some of the equipment may cost more for the 5-gallon aquarium if it is not a popular item that is mass produced. Gallon for gallon, a small tank costs more than a large one. Therefore buying a very small tank is not really economical at all.

There are two types of stands available in most pet shops, wrought iron and wood. You will find the iron stands to be less expensive, although many of the wooden stands are competitively priced. The iron stands are open on all sides, while many of the wooden models are enclosed to give a (cabinet-like appearance with doors in front.

It is a good idea if you can afford it. The equipment required is somewhat more expensive, requiring heavier- duty heating and filtering units than the smaller, average- size tank. But remember that if something goes wrong due to mishandling, a change often becomes necessary. And it is quite a chore to change all the water and clean the gravel in a 40- or 50-gallon tank.

A large tank has certain decided advantages. A large number of fishes can be kept without overcrowding, and they will usually grow better than when kept in smaller confines. There are several species of fishes which tend to be pugnacious when crowded into a small aquarium. Many of these same fishes are quite peaceful when given more “fin room.” Scenically, an artistic person can really let himself go with a large aquarium. A little imagination can transform a large aquarium into an enchanting underwater garden, with grottoes and mountains, valleys, and even lawns. A lovely little plant, Micro Sagittaria, never grows more than an inch or so high. Planted toward the front of an aquarium, it soon covers the bottom with a luxuriant green lawn. Best of all, it requires no mowing!

Using an Aquarium Siphon

A siphon is a tube, made of rubber or plastic, by means of which water can be drawn out of the aquarium into a container which is at a lower level. A convenient size t use is a 5-foot length of 1-inch inside diameter heavy rubber tubing. Heavy-wall tubing is advisable to prevent kinking and collapsing. There are three methods for starting a siphon:

1. Holding the tube to form a U, put one end under the faucet. When water runs out of the other end, indicating that the tube is full of water, cover both openings with your thumbs. Hold one end underwater in the aquarium and the other end in a bucket lower than the aquarium. Release both ends. Once the flow has started, it will continue automatically.

2. Immerse the entire tube in a container of water, keeping the open ends higher than the center so that all the air runs out of it. Place a thumb over each opening, and then release both ends.

3. The method most frequently used by experts, because it is fastest, should first be practiced with a container of clear water. It involves placing one end of the siphon tube in the water to be siphoned out. The balance of the tube is allowed to hang down. Suck on the lower end until the flow starts, and then quickly drop it into the bucket. A little practice will enable you to tell by the sudden easing in the resistance of the suction pull that the water has come over the top of the loop and is starting down. It will, however, take a little practice so you won’t get a mouthful of water.

An 8- to 10-inch piece of rigid plastic tubing in the end of the siphon hose makes it easier to control and move. The short end in the aquarium is held in the right hand, which guides it over the bottom. The left hand directs the flow into the basin or bucket and regulates the flow, either by pinching the hose or by moving the thumb over the outlet opening.

Stop the flow, hold the suction end about 1 inch over some debris at the bottom of the aquarium, and release the flow momentarily. The debris will be sucked up like magic. By controlling the flow, a maximum of dirt and a minimum of water can be removed. A siphon can be used as a cleansing tool, as a means of emptying the aquarium of water, and as a way of removing gravel - providing the tube is wide enough. In any of these jobs, practice develops control. By putting a funnel at the siphon intake, the siphon will not pick up gravel - only the lighter material.

Surprisingly enough, fishes are seldom sucked up in a siphon. Ordinarily, they avoid it when they feel the suction, although when an aquarium is being emptied, fishes that remain as the water is lowered become panicky and will rush up the siphon tube. The rapid trip rarely injures them so long as they land in a container of water and not on a hard surface like the floor.

Lifting the siphon out of the water without closing the ends will empty the tube and break the suction. Should the siphon tube become clogged and resist efforts to blow it out, place it on the floor and walk along it to crush the clogging material.

Feeding your Tropical Fish

Any type of fish available out there is part of one of the three main types of feeders. This is true for any type of fish, be it coral, anemone or crustacean.

The carnivores. Carnivore fish will have other fish as their main source of food. Carnivores are either scavengers or predators. A predator fish will enjoy hunting their own food, so there is a chance they will not eat what you offer them. In many cases predators will only need to eat once a couple of days. As for scavenger carnivores, they will eat pretty much anything, like what predators leave behind.

The herbivores. These are the fish that will eat algae and marine plants. They will keep moving around, getting any food they find.

The omnivores. The omnivores are a mix between herbivores and carnivores. They will enjoy eating crustaceans, plants, corals, algae and invertebrates.

When you put food inside the aquarium, you should know that some fish will not give much attention to it. If they’re used with ocean life, where they’re not fed, they will not be used to someone giving them food. Most will learn in time to eat the food you give them, but some of them will not.

Omnivores and herbivores are the fish that will adapt to an aquarium faster. Still, fish like the Angels, that are used to find food on the floor of the ocean, will take a bit longer to begin eating what you give them.

How often should a fish be fed? The best would be to give them food only once a day and the quantity of the food should be enough for them to finish it after one minute of eating. It might seem like a small quantity of food, but if they don’t eat it in under a minute, they’re probably not hungry enough.

The importance of aeration for tropical fish

Everyone knows that the natural habitat for fish is a lake or rivers. Both have large surfaces where fish can get to receive their oxygen supply. As you can guess, an aquarium doesn’t offer fish the same possibilities when it comes to water surface. The habitat has less movement and the surface area where they can get oxygen is smaller. That’s why it’s important to make sure that fish can get oxygen from other sources as well.

Aeration is the artificial oxygen providing process. The process consists only of re-oxygenating the aquarium water. The system used for aeration usually consists of airstone, regulator diffusers or tubing clamp that pumps air.

There are plenty of types of air pumps, of different sizes and shapes. The one that most people use is a Taiwanese one, called tecax air pump. Another popular choice is the super 555, fabricated in India. They cost less but they’re not as resistant. You can also find versions built in France and UK, but they’re usually a bit more expensive.

The air pump should be hooked to a material that doesn’t vibrate and it’s above the level of the water. The aeration materials that I mentioned before can work well to aerate the aquarium. If the tank is small, you only need to use a simple air pump, through an air tube made of rubber, to an air stone. The air will be blown into the water by this system and provide fish with the oxygen they need.