Using are 10 gal air pump in 29 gal tank

[Eve]

Is it ok to use an air pump designed for a 10 gallon tank in a 29 gallon tank? When I first set up my new tank I realized my pump was made for a smaller tank size, but I hooked it up to a long bottom-seated air stone and it works fine. This should be fine right?

Thank you so much! I really don't know what I'd do without this site (and how my fish would be doing for that matter).

 

[Hannys_Papa]

Yeah its fine. I am unsure why they rate pumps for tank sizes - it just doesnt make any sense. After all if you have a HOB filter it does all the moving water around, surface agitation and oxygenation of the water.
In fact most people will say that airstones, bubblestrips etc are purely for aesthetics - they arent necessary to have oxygen in your tank.
Now that my tank has plants in it i took my air strip out to save the little CO2 thats in the water for the plants and not drive it out of the water.

 

[mvigor]

I'm sure that air pumps being rated for tank size by gallons is because they are calculating the water pressure at the bottom of a tank.

For example, an airstone at the bottom of a 29 gallon tank (or larger) would have a heavy water pressure on it. The weight of the tank water would try to press the air back up out of the tube and force water back into the pump. The little "10 gallon" air pump would have to work hard to combat this force and make air come out into the tank instead.

If the 10 gallon rated air pump is put into deeper and deeper, larger and larger tanks, you will eventually find a size where it won't physically be able to pump air out at all and the tank water would creep up and into the pump instead.

 

[Hannys_Papa]

Sounds logical - i have however seen a "10G pump" powering a 10" bubble strip in a 40something G hex tank (very deep compared to most tanks) - and the way it looked it must've been doing that for years.

As usual it was just my 2 cent - i think the fact eve was using this setup for a while already proves it works. My impression was that she wondered if her air pump might be "undersized" for the tank - which i dont think it is.

Maybe the 10G pump cant handle it anymore if you drop it in a 4ft deep tank... ??? No experience with that so your theory might very well be true then mvigor.

 

[mvigor]

I was speaking more in general theoretical terms. It would probably be hard to find a place in a house with enough water pressure so stop an air pump from pumping some bubbles. Just the other day I was aerating a 30 gallon rubbermaid tub full of water and driftwood with the pump that came in a set to power the UGF in a 1 gallon Betta tank. I didn't think much of it, but it was probably working a little harder than it would have to work in a 1 gallon tank.