Do air pumps really provide oxygen into the water?

[daveman12345]

I put a new canister filter in today that was underwater. My fish were breathing out of their mouths showing signs of stress. When I put back my HOB filter, they were normal, and when I went back to the canister they were stressed again. So, I came to the conclusion that their might not be enough oxygen in the tank. I've always thought that "air pumps" provided oxygen into the tank, though I just did some research that said this is only a myth. So, I took my canister filter and for the water flowing back into the tank, I put it above the water so that it could push oxygen into the tank.

Now, can someone tell me if what I'm doing is right?

 

[rallysman]

What you're doing now is fine, but air pumps do provide oxygen. Chances are that your canister filter isn't breaking the surface tension which could lead to depleted O2 levels. The bubbles from an air pump diffuse O2 back into the water and also break the surface which allows for gas exchange.

With the canister return above the water level you're breaking the surface which will also allow for gas exchange.

 

[daveman12345]

P.S. Now I'm questioning whether or not having a waterfall into the tank is even providing oxygen. Please help!

 

[daveman12345]

What you're doing now is fine, but air pumps do provide oxygen. Chances are that your canister filter isn't breaking the surface tension which could lead to depleted O2 levels. The bubbles from an air pump diffuse O2 back into the water and also break the surface which allows for gas exchange.

With the canister return above the water level you're breaking the surface which will also allow for gas exchange.

OK so here's a couple of options that you believe is fine. Also in the end I have links to pages where it says that "air pumps do not put oxygen into the tank".

Option 1: Canister return below water level with an air pump will provide enough oxygen?

Option 2: Canister filter above water level without an air pump will provide enough oxygen?

Here's the links I read about air pumps not putting any oxygen in the water... can others chime in as well?
http://www.firsttankguide.net/airpump.php

 

[StripeGirl]

air pumps produce air thus the name Air Pump?

 

[Dr Joe]

I've got to type faster
So how are the fish acting now?

Returning it that way is fine.

Now, you asked about "Do air pumps really provide oxygen into the water?" but you didn't say if you have or tried one. Yes, aeration replenishes oxygen in the water, If you use an air stone (limewood is best) and a decent air source they do much better that a HOB splashing return water back into the tank. It also helps with off-gassing.

You weren't just putting too much current in the tank with the canister were you?

Dr Joe

.

 

[Jfitz]

P.S. Now I'm questioning whether or not having a waterfall into the tank is even providing oxygen. Please help!

all that will do is break the surface tension. I don't know if thats what you were talking about, but if you're talking about rallysman quote saying that breaking the surface tension oxygenates the water then go for it

 

[rallysman]

Gas exchange - where the water dissolves oxygen and other gases from the air and releases excess carbon dioxide and other gases to the air - occurs over any and all surface area where the water has contact with air. By increasing the surface area of the water, each bubble gives the water further opportunity to release carbon dioxide and take up oxygen. However, this improvement from an air pump is shadowed by the improvement in circulation that the air pump can effect. The improved circulation will move highly oxygenated water from the surface lower in the tank allowing water with more carbon dioxide and less oxygen to the surface of the tank where id can release its carbon dioxide and take up oxygen. Of course, if you already have a good filter that is providing sufficient water circulation, then the benefit you will receive from an air pump is minimal.

What I got from your (poorly worded) link, is that if there isn't much surface agitation (which increases surface area), then there wont be much gas exchange. When there isn't much gas exchange, then oxygen levels will be reduced. I may have read it wrong, but when I think of it that way it makes sense. Think about stagnant water. Even if there is flow under the surface, it won't do much if the surface is calm enough to develop a film.

The link states that good circulation will be enough. Without breaking the surface it might not be enough.

With that said, I think you kind of answered your own question. When you break the surface with your HOB, the fish are fine. When you don't they're not fine.

 

[daveman12345]

Hey, I really don't understand what some of the posts above meant if you're trying to discredit me as a newbie or something. Like I said, if you read the link I provided, here is what it clearly states:

One of the most common misconceptions in the aquarium hobby, possibly second only to "fish will not outgrow their aquarium", is that you need an air pump and air stones to provide sufficient oxygenation to that tank to keep the fish healthy, and that the air pump provides oxygen to the water. In fact, the air pump is not necessary to keeping fish, except as noted above. An air pump will not directly put oxygen into the water, what it will do is two things:

1. Increase surface area
2. Improve circulation

Now, I may be a newb but I have a pretty valid point, and I'm more concerned about my fish than anything else. So, I'd appreciate any help at this point.

So, you Rallysman and Dr Joe... you're saying that contrary to what that web site says, that by having an air pump in the tank then oxygen is being created in the tank?

Also, lastly let me clarify that what I have is an air pump and an air stone. What I have is 1. the air pump that pushes air through a tube that leads to 2. a long stick that's about 2 feet long with a bunch of holes that pushes bubbles into the tank.

Now, please let me know if my tank is being oxygenated sufficiently based on the two options I listed on post #4. My Arowana's will thank you!

 

[daveman12345]

What I got from your (poorly worded) link, is that if there isn't much surface agitation (which increases surface area), then there wont be much gas exchange. When there isn't much gas exchange, then oxygen levels will be reduced. I may have read it wrong, but when I think of it that way it makes sense. Think about stagnant water. Even if there is flow under the surface, it won't do much if the surface is calm enough to develop a film.

The link states that good circulation will be enough. Without breaking the surface it might not be enough.

With that said, I think you kind of answered your own question. When you break the surface with your HOB, the fish are fine. When you don't they're not fine.

Right. So, by having the canister flow of water go inside of the water and not above it, causing the waterfall, then it wouldn't provide enough oxygen into the tank even with an "air pump"? I'm basically trying to confirm that an "air pump provides oxygen into a tank" is a myth, and that you pro's here at MFK confirm that it's a myth.

Let me make it clear: my original goal was to have it set up this way to provide minimal surface agitation so that my Arowana's could freely roam the surface of the tank without the agitation.