How does a cylinder pump operate in a Fish Tank?

A motor is connected by a leather belt to a flywheel. As the flywheel turns, it actuates a piston which forces air out through a cylinder. Some larger models have two cylinders with the flywheel located between them. As one piston enters its cylinder the other is withdrawn, thus providing a continuous flow of air. The amount of air and the air pressure delivered by a cylinder pump are determined by the size of the cylinder, the speed of the motor and the size of the flywheel. The standard motor is from 1/150th to 1/75th horsepower. The volume of air given off by a cylinder pump can, in some models, be regulated by adjusting the angle at which the piston enters the cylinder.

First of all - power. Cylinder pumps deliver considerably more air and give more pressure than the diaphragm type. They are less subject to breakdowns, and can usually be repaired by the owner with replacement parts, which are available at the pet shop. This eliminates the delay and inconvenience required for sending the pump back to the manufacturer for repair.

When purchasing a cylinder pump, always ask for a manufacturer’s instruction sheet, which details the proper oiling and adjustment procedures for oil holes while turning the motor by hand. Continue this until the cleaning fluid runs through clean. Allow several Fours for the carbon tetrachloride to dry completely both inside and out. Make sure that the motor is re-oiled before being put back into use. The cleaning fluid, of course, will have removed all the oil as well as the dirt.

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.

What is a vibrator pump for a tropical fish aquarium?

The same principle of make-and-break current operating in the common doorbell also applies in operating a rubber, leather, or plastic diaphragm which fits over the air chamber of the pump. As the diaphragm moves up and down, air is forced out through one-way valves.

Most diaphragm pumps have a low air pressure but an adequate air volume. They are usually equipped with a knob which controls the volume of air put out. Diaphragm pumps do not usually have so long a life as do cylinder pumps, nor are they so powerful. They are usually less expensive, and for the hobbyist with one or two small-to medium-sized tanks they are perfectly adequate. They have the advantage of no outside moving parts and do not give off any heat. Nor do they require any oiling or other care. Should they break down, it is usually necessary to return them to the manufacturer for repair. In many cases the guarantee specifies that opening the case voids the guarantee.

Another point of information about vibrator pumps: they must be placed on a firm yet resilient surface, not an unyielding one such as a wall, a table top, or a loose floor board. A sponge rubber pad makes an excellent mounting for a vibrator pump. Such material also helps to eliminate the hum which is an unfortunate feature of some vibrator pumps.

Some diaphragm pumps are very cheap, while others are comparatively expensive. In purchasing pumps, as with other items, you get what you pay for. The lower-priced pumps are not necessarily a better buy. Often they are cheap merchandise offered for sale at a low price. In order to compete, some manufacturers sacrifice quality and reliability so that they can offer a low price. Shop carefully before you purchase a pump, especially if you want it to provide long service. Consider only nationally advertised products.

Vibrator pumps require no care; cylinder pumps should be oiled regularly. Some vibrator air pump features an adjustable output of air, allowing you to control exactly how much air is released.