Airation

[Brewster'sLife]

This is my first time having a community tank and I realize it should probably have a bubbler of some kind but wasn't sure how big of one or anything. It's a 29g planted tank that currently has 4 bronze corys, will eventually have danios and maybe rasboras.

 

[Carolyn N]

In my community tank I have a sponge filter and a HOB (hang on back) filter. For the sponge filter you need an air pump and you can also have an air stone if desired. The air pumps are fairly inexpensive. You need the pump, a gang valve for splitting the air into two lines to either another tank, two air stones, or sponge filter and air stone. Your choice. It is not a necessity. But, it depends on your type of filtration and number of fish if it is necessary for the added water circulation.

 

[I nEEd mEnTAl HeLP]

A bubbler is to provide aeration. If you have a filter, you probably already have enough aeration. If you do add a bubbler though, I recommend getting a sponge filter since its more oxygen and filtration.

 

[Retired Viking]

I agree a air stone is a simple and effective way to help aeration.

 

[Byron]

If your concern is the oxygen/CO2 gas exchange at the surface, you need tohave sufficient surface disturbance. "Bubblers" do not provide this effectively. Use the filter return to agitate the surface at one end of the tank; you want a sort of rippling movement. This is especially important in planted tanks because at night the CO2 can increase quite a bit, and fish respiration may be affected.

The visual aspect of bubble wands and similar is up to you, but I have come across studies where the actual surface disturbance from these was much less than we are often led to believe.

 

[Retired Viking]

If your concern is the oxygen/CO2 gas exchange at the surface, you need tohave sufficient surface disturbance. "Bubblers" do not provide this effectively. Use the filter return to agitate the surface at one end of the tank; you want a sort of rippling movement. This is especially important in planted tanks because at night the CO2 can increase quite a bit, and fish respiration may be affected.

The visual aspect of bubble wands and similar is up to you, but I have come across studies where the actual surface disturbance from these was much less than we are often led to believe.

So would a HOB filter with a waterfall be better?

 

[Byron]

So would a HOB filter with a waterfall be better?

Yes, because it is creating surface disturbance. So will the filter return of a canister filter--sometimes the spray bar works well, sometimes you might want to remove that and just use the spigot for more movement. I achieve good surface disturbance in my tanks with an Aqueon Qjuiet Flow filter, simply by adjusting the direction so the water flow is aimed upward and ripples the surface.

I do not like HOB filters, I used them back in the 1980's but not since. But properly operating, they certainly create surface disturbance.

 

[Retired Viking]

Yes, because it is creating surface disturbance. So will the filter return of a canister filter--sometimes the spray bar works well, sometimes you might want to remove that and just use the spigot for more movement. I achieve good surface disturbance in my tanks with an Aqueon Qjuiet Flow filter, simply by adjusting the direction so the water flow is aimed upward and ripples the surface.

I do not like HOB filters, I used them back in the 1980's but not since. But properly operating, they certainly create surface disturbance.

I have not used them for many years either, was just wondering. I am currently using UGF and sponge filters. With all my plants you have me wondering about oxygen levels.

 

[Byron]

I have not used them for many years either, was just wondering. I am currently using UGF and sponge filters. With all my plants you have me wondering about oxygen levels.

This is worth wondering about. Several months ago I happened to be sitting in front of my 70g tank which housed my group of 60 Corydoras. It was just after the tank lights came on, so not the usual time for me to be in the fish room. I noticed the cories were all respirating much faster than normal. I had seen this once before about five or six years previous in another tank, and in that case it turned out to be a partially clogged filter reducing the flow and thus the gas exchange. The flow this time seemed OK, but it got me thinking if there was enough surface disturbance to provide a good exchange of oxygen/CO2 during the night when the CO2 rebuilds, so I adjusted the filter return (removed the spray bar and just used the spigot) and for the next several mornings, no more heavy respiration. And much less surface breaching too.

 

[Retired Viking]

Thanks I will keep a closer watch on this.

 

[ChefAlex]

Just a note on air pumps and water oxygenation:

Yes, air pumps do oxygenate water. Their lack of surface agitation has nothing to do with how they perform. Via diffused aeration, in our case air pumps in home aquariums, oxygenated bubbles dissolve oxygen into the water column simply by mixing with water. The diffusers we use for injecting c02 in planted tanks work in exactly the same method.

That being said, not all air pumps are being utilized for maximum performance. Contact time, bubble size and air flow rates are all factors. Ideally, an air pump would be used with diffuser creating the finest mist of bubbles possible (these dissolve oxygen much faster than large bubbles) and contact time in the water time would be increased by placing the diffuser as low as possible in the aquarium (or by any other number of means, IE think of how different protein skimmer designs maximize contact time in different ways). Any literature on diffused aeration used in a number of fields will be eye opening for those who are uncertain of air pump oxygenation efficacy in aquaria.

I think the general shunning of air pumps nowadays has more to do with people not understanding that surface agitation isn’t needed for diffused aeration. Yes, surface agitation is a more efficient way of aerating an aquarium (generally) but air pumps used properly are just are valuable.

Just my 2 cents