Do i really need an air pump( the one that blows air in the water and creates bubbles) for saltwater fish?

Question

the air pumps is annoying... i was just wondering what will happed if i remove the air pump?

Answer 1

Probably not. The common misconception is that an airstone will help add oxygen to the tank's water. The fact of the matter is, it isn't the bubbles that causes the addition of oxygen to the water, it is the movement of water at the interface between the water surface and the air that adds Oxygen (and removes Carbon Dioxide) from the water.

It works like this. Gases like Oxygen and Carbon Dioxide move fairly rapidly between air and water by diffusion to establish an equilibrium. What that means is this. Gases dissolved in a liquid exert a pressure at the waters surface as they try to escape. The more gas dissolved in the water, the greater the pressure it exerts. Meanwhile, that same gas in the air exerts a pressure pushing the gas into the water. (OK, so that is a simplification, it illustrates the point). The movement of gasses between the air and the water stops when these two pressures are equal. In the deeper parts of the tank, Oxygen is being used and Carbon Dioxide produced by the organisms in the tank. This lowers the amount of these gases in the deeper areas of the aquarium. This causes the gases at the surtface to diffuse down into the tank to keep things equal everywhere. As long as the rate of movement of gas into the deeper parts of the tank equals the rate the gases are being used or produced, everything will remain stable. The problem is that the movement of gases down into the water column is relatively slow. Thus, the rate the gases are used could exceed the rate that the gases move down from the surface. That would result in a shortage of Oxygen below the surface and an excess of Carbon Dioxide (which would result in a lower pH since dissolved Carbon Dioxide actually forms Carbonic Acid). So, if there is no movement at the water's surface the rate that gasses move down the water column is completely dependent on the rate of diffusion of these gases. Saying it a different way, as the Oxygen is used up in the tank, more diffuses down from the surface but only as fast as the gas molecules can work their way through the water molecules to get there.

You can illustrate this easily. Take a glass of water and sit it on a table. Then place a single drop of food coloring on the surface. You will see that it takes a LONG time for that food coloring to move through all of the water. It gets there eventually, but it takes a long time.

What if you stirred the water with the food coloring? It diffuses MUCH more rapidly. That is what we are trying to acheive. A way to move the dissolved gases around in the water column. It gets a bit more complicated though because, unlike our food coloring example, the Oxygen and Carbon Dioxide are being used up by the various life forms in the water. So those gases need to be replaced as they are being used up. The movement of water at the surface allows this to happen more rapidly by driving the Oxygen depleted and Carbon Dioxide laden water from the depths of the tank to the surface where the Carbon Dioxide and Oxygen will be exposed to the pressure of these gases in the air. Since we have added Carbon Dioxide to the water that came up from deeper in the tank, the pressure of the Carbon Dioxide trying to leave the water will now be higher then the pressure of the Carbon Dioxide in the air trying to push more into the water and Carbon Dioxide will then leave the water moving into the air until the pressures are equal again. Thus, Carbon Dioxide leaves the aquarium. The opposite occurs with Oxygen. Movement at the surface then, exposes more water in any given time to the surface air allowing for more gas to enter or leave the aquarium in any given length of time. Thus, gas exchange can occur more efficiently since, instead of relying solely on the diffusion from the surface to the deeper waters in the tank one would have with no surface movement, one now has a situation where the deeper water with less Oxygen and more Carbon Dioxide is moved to the surface for rapid equalization with the atmospheric air.

So, this is really about circulation of water from deeper in the tank to the surface. Anything that causes currents in the aquarium will have the same effect, be that an air stone, a filter, or a powerhead.

So to answer your question, do you really need an air pump? If that is your only source of water movement, yes you do. If you have another source of water movement (and that would almost certainly be the case in a well set up tank) then you don't need one, and probably shouldn't have one.

(I could get more technical and discuss the production of Carbonic Acid as Carbon Dioxide dissolves and its effects on pH, but that gets WAYYYYY complicated! as if this wasn;t complicated enough!)

Pretty cool how a simple thing like a fish tank can illustrate some neat scientific principles isn't it?

Answer 2

You don't need a bubbler (airstone) as long as you have some type of filtration. The filter will move the surface of the water and this is where oxygen is actually dissolved into the water - the bubbles don't do much because the don't have enough time in contact with the water before they pop at the surface.

The air can damage or kill the organisms that live under the live rock if the air becomes trapped.

I would disagree with saltwater fish not needing as much oxygen as freshwater, however. With the movement of waves from the wind and tides, saltwater fish are exposed to more dissolved oxygen than some of the freshwater fish. This is especially true of fish like tangs which are very sensitive to the amount of oxygen in a tank.

So as long as you have a filter that will make ripples across the surface of the water in your tank (and maybe a powerhead to distribute the oxygenated water to the bottom if your tank is deep) it should be okay to turn the air pump off.

Answer 3

contrary to what most people think, bubbles from air pumps only minimally increase the amount of oxygen in the water. they're mostly for decorative purposes. air/water exchange occurs mostly at the water surface. if u have a good filter such as a wet/dry filter or a pump/filter that disrupts the water surface, then u should have adequate levels of oxygen in the water. the only time u would need an air pump for a saltwater aquarium is for the protein skimmer.

Answer 4

well if you have a good protien skimmer it will put enough oxygen in the tank as well as enough current so the surface of the water is disturbed causeing oxygen to flow into the tank as well. Otherwise id reccomend keeping the air pump with the bubbles in fact its never a bad idea to add more oxygen to the tank. if you dont like the way it looks with an airstone stuck to the wall or it is prodicing so many bubbles that the tank is almost clouded with bubbles than get a valve that will limit the amount of bubbles to a more reasonable amount or try putting the air stone under some rock work so it has a prettier effect.

Answer 5

Water temperature too warm or cold, dirty etc will affect and lower down the oxygen level in the water. Air pump and bubble wand brings extra oxygen into the water and make it easier for fishes to breathe. And also a "natural decoration" makes the tank more outstanding.

Answer 6

No, you really don't. You should have a good filter system and that will take care of your fish's oxygen needs. The bubbles are more for your amusement than providing for the needs of the fish.

If you don't have a filter, your salt water fish won't live long, air pump or not.

Answer 7

depends on your setup, if the air pump is in no way attcahed to your filtration you can remove it. it is best to add some powerheads though, try ot aim for 10-20x tank flow. i dont like using an air pump, i have heard that it adds carbon dioxide to fast and can cause a drop in your alkalinity, but have never added an air stone to a saltewater tank to see if that was true, but i have heard from a few sources that is the case

Answer 8

I agree with some of the others if you have a good filter you dont need it.
also make sure you dont have an air stone hooked up to it in your tank since the salt water will brake it down really fast and it could damage your filter

Answer 9

bubblers are typically looked down upon with SW tanks. they are abtrusive to the microfauna that live in live rock and can actually kill beneficial bacteria if left in mass.
if you have adaquate surface aggitaion and a good filter with plenty of flow in the tank that's all the oxygen that's required, SW don't need as much O2 as FW do, it's a fact.

Answer 10

the airpump simulates the natural oxygen that is being dispersed under water from the core of the earth, its very necessary for almost all marine life to be able to access air in their system. depriving them of air will kill most of them. you should be able to find a much quieter motor from different stores or maybe the rubber gasket from your motor is a bit stiff or old causing harder vibration which causes the annoying noise, try replacing it first.