Power heads vs airstones

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Caliban07

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Can someone please explain to me which whether or not air stones add oxygen to the water. My understanding is the the air is trapped in the bubble and us released at the surface. Does a sufficient amount of gas exchange occur here that oxygenates the water? And if minimal, would this constant action be enough to make a difference to the oxygen levels?

Is it better to use a power head to cause surface movement to aid oxygen levels or if parameters are good. Is there any need to use any? I guess it all depends in stocking levels plants etc but what are your thoughts?
 
I've never been bothered much worrying about dissolved oxygen levels. All I do is have a power filter aimed at the surface for agitation. Air stones are a pain imo. I'd rather just have one powered appliance in my tank.

A quick google and it seems to measure oxygen would be costly. It would be cool if someone has done a comparison of aerators.

Was also reading scum on the surface of the water impedes gas exchange. Nice excuse for me to buy a skimmer. :)
 
Airstones

Can someone please explain to me which whether or not air stones add oxygen to the water. My understanding is the the air is trapped in the bubble and us released at the surface. Does a sufficient amount of gas exchange occur here that oxygenates the water? And if minimal, would this constant action be enough to make a difference to the oxygen levels?

Is it better to use a power head to cause surface movement to aid oxygen levels or if parameters are good. Is there any need to use any? I guess it all depends in stocking levels plants etc but what are your thoughts?

Hello Cal...

I'll take a shot at your question. Airstones are mainly for show. The tiny bubbles have no surface area, so when they rise to the top, they make tiny waves that really don't do much to mix oxygen into the tank water and allow carbon dioxide to escape (gas exchange). Even a lot of tiny bubbles don't do much. It would be better to remove the airstone and place the end of the plastic tube at the bottom. The much larger bubbles will move the surface water and create the surface movement you want.

You don't need the airstone. A good power filter with a gallon per hour rating (gph) of 4 to 6 times the volume of your tank in gallons is all you need. Add large, weekly water changes to the mix and your fish and plants will be healthy.

B
 
The smaller bubbles will help diffuse more o2 into the water. With smaller bubbles the surface area is increased by a huge amount which facilitates this.

The airstone will also greatly increase surface agitation allowing more co2 to be degassed from the tank. They aren't necessary in general use but I firmly believe that it's always a good idea to keep one whether you are medicating, heat treating, or your filter fails.
 
Hello Cal... I'll take a shot at your question. Airstones are mainly for show. The tiny bubbles have no surface area, so when they rise to the top, they make tiny waves that really don't do much to mix oxygen into the tank water and allow carbon dioxide to escape (gas exchange). Even a lot of tiny bubbles don't do much. It would be better to remove the airstone and place the end of the plastic tube at the bottom. The much larger bubbles will move the surface water and create the surface movement you want. You don't need the airstone. A good power filter with a gallon per hour rating (gph) of 4 to 6 times the volume of your tank in gallons is all you need. Add large, weekly water changes to the mix and your fish and plants will be healthy. B

So are you saying it's better/healthier for the fish if it's just the tube blowing our bubbles and not the airstone you connect it too? The only reason I ever hook up airstones is becuase I though fish needed them for oxygen
 
Use one or two powerheads depending on the tank size and have them aimed toward the surface the agitation is whats needed to aid in the gas exchanges at the surface. I haven't used an air stone in 30 years.
 
Use one or two powerheads depending on the tank size and have them aimed toward the surface the agitation is whats needed to aid in the gas exchanges at the surface. I haven't used an air stone in 30 years.

Are power heads loud ? Which brand do you recommend for a 75 gallon
 
Most sponge powerheads will have an option to attach an airline to them so air will be blown into outake. I always use an airstone, not because im sure i need to but because im not 100% sure i dont.

Powerheads should be completely silent.
 
Last edited:
Well like I said I haven't used air stones in years.I have two powerheads plus the main pump moving the water in my 90 salt and I think my fish are as healthy as anyones so take it from there.
 
Hello Cal...

I'll take a shot at your question. Airstones are mainly for show. The tiny bubbles have no surface area, so when they rise to the top, they make tiny waves that really don't do much to mix oxygen into the tank water and allow carbon dioxide to escape (gas exchange). Even a lot of tiny bubbles don't do much. It would be better to remove the airstone and place the end of the plastic tube at the bottom. The much larger bubbles will move the surface water and create the surface movement you want.

You don't need the airstone. A good power filter with a gallon per hour rating (gph) of 4 to 6 times the volume of your tank in gallons is all you need. Add large, weekly water changes to the mix and your fish and plants will be healthy.

B
I agree with BBradbury. I believe they are purely cosmetic in your main tank but are used in fry tanks and hospital tanks. It's completely personal imo, some people love them, some hate them. It's the pump that does my head in!!
 
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