Is it possible to over-aerate?

HI - this is my first post. I have a 12g freshwater community tank with no real plants. I have an appropriate size air pump feeding a flexible bubble stick producing a "wall" of bubbles on the back wall. The tank has a number of (nice) fake plants and all of them are covered with little bubbles. The tank is about 3 weeks old (started with bio-spira) and the fish all seem happy and healthy and my multi-test dipstick always comes out just about perfect. Is there a potential problem here with too much aeration or is that impossible in a non-planted tank? Thanks so much!

 

There is no such thing as too much aeration in a non-planted or even planted tank, as live plants utilize oxygen during the night cycle. The only drawback to aeration of a planted tank is that it drives off CO2 quicker.

The only time aeration is bad is when transporting fish in a small container as it allows the water to become toxic, quicker.

This is my understanding so if I'm wrong, someone please let me know.

 

actually a bubble wall doesn't make as much aeration as you think... it's nice too look at and you see lots of bubbles but it surface aggitation that creates the most oxygen. If you ran a small pump to shoot water along the surface from one end to the other in say a 30g, or ran a HUGE bubble wall stick at the rear of the tank, it would actually be the small pump that would produce more O2 since there is more happening at the surface tension point. never the less, bubble walls are very attractive when done right and do provide O2, but I don't think you have anything to worry about with over-oxygenating your fish

 

Thanks!

 

Welcome to Fishlore!!

 

Welcome to fishlore!!
Actually bubblers, bubblewalls etc don't bleed C02 off unless your are running CO2.
Through Osmosis CO2 will go to where the least concentration is in an effort to equalize the concentration. So if you have a little surface aggitation you may actually be pulling CO2 in from the atmosphere because the water concentration will usually be lower than the air.
Now if your running CO2 injection surface air would bleed CO2 off.
Carol

 

There is also a saturation point for oxygen in the water, which means the water can physically only hold so much oxygen before it is "full". I don't know right off hand of any situations where even saturation point oxygen would be bad for fish or plants.

 

welcome to fishlore! glad to see you looking out for your fish.

 

Welcome to Fishlore!! Natalie

 

Actually you can. It's caused oxygen supersaturation. It can cause what's known as air bubble disease, which means that air bubbles form inside the fish (including eyes and organs) and will cause great pain. You know you're oversaturated if small bubbles stick to the fish and ornaments. One thing that generally causes oversaturation is a filter outlet that lets in air from the outside. So I just switch mine on at night, when the plants release CO2, and I switch if off in the morning.

 

I really don't think bubblers, bubble walls etc are in any danger of causing oxygen saturation or gas bubble disease in our aquaria for the simple reason that the oxygen through osmosis would move to the less oxygenated air around the aquarium.
If liquid oxygen were mixed in the aquarium, or pure oxygen were injected in an effort to raise the Dissolved Oxygen (DO) then it would have to be monitored closely. But
a situation that would come closer to affecting us... when filling an aquarium for the first time(especially if using cold water) little bubbles form on the sides of the tank and on decor. This is super saturation , this is why it needs to set for about 24 hrs after filling to out gas (let some of the oxygen cross into the air )

Carol

 

That's true, Carol. The more risky things are not to disturb the water enough after putting it in (since it comes from higher pressure in the tap) and filters that take air in directly from the outside. Just watch out if you see lots of tiny bubbles sticking to stuff.

 

Theres not too much chance of us having too much oxygen in our aquariums I have one of these and it is designed to add oxygen to the water and have never had a problem. Since our aquariums are not sealed just the simple things we do are not going to add enough oxygen to be concerned as excess will cross into the air around us.

Carol

 

Those tons of tiny bubbles that come after waterchanges are not something to worry about for any reason. We have them show up in EVERYone of our tanks after we change the water and go on with business as usual.

You could seriously put a line from an oxygen tank into your aquarium on full blast and other than making a mess with splashing water all you would accomplish is possibly reaching saturation point. Once water has its saturation point of anything it will not hold more, it will bleed off the surface as quick as it needs to.

Super saturation is a problem when it comes to nitrogen, but not a saturation in the water, it is a saturation in the human body. It causes a disorder known as 'bends' for divers who are too deep and come up to the surface to quickly.

 

I found some really interesting information

last paragraph states bubblers could not add enough o2 to be a problem.
Although the whole article is very interesting.
Below is quoted from

The recommended minimum dissolved oxygen requirements are as follows:

Cold water fish - 6 mg per litre
Tropical freshwater - 5 mg per litre
Tropical marine - 5 mg per litre

It is worth bearing in mind these values are minimum requirements for healthy growth, tissue repair and reproduction.
hope this helps
carol

 

Supersaturation requires pressure.

This problem can be encountered for the very short period of time it takes the oxygen coming from a high pressure environment ( well/ city pipes) to de-gas thru the water and into the air.

In almost 30 years of fishkeeping using a well, I have never had any problems from this.

 

I mean tiny bubbles that continue to stick. Not just after a water change.

Indeed, I've never heard of a problem from an airstone/wand. I was referring to the type of filter that blows air from the outside in the form of tiny bubbles that stick to absolutely everything permanently. They're really annoying.

Those tons of tiny bubbles that come after waterchanges are not something to worry about for any reason. We have them show up in EVERYone of our tanks after we change the water and go on with business as usual.

You could seriously put a line from an oxygen tank into your aquarium on full blast and other than making a mess with splashing water all you would accomplish is possibly reaching saturation point. Once water has its saturation point of anything it will not hold more, it will bleed off the surface as quick as it needs to.

Super saturation is a problem when it comes to nitrogen, but not a saturation in the water, it is a saturation in the human body. It causes a disorder known as 'bends' for divers who are too deep and come up to the surface to quickly.

 

I am a science nut. I can guarantee you that there is no way to supersaturate oxygen (or anything else) in an aquarium. As mentioned above, pressure (or drastic changes to such things as temperature) is generally required to achieve supersaturation. But in an open system such as an aquarium, any movement at all on the surface will immediately release all the oxygen above the saturation point.

 

This has been a very interesting read.

I've considered adding a small bubble wand in my 10 gallon tank that is a natural planted tank. I was told different things when it comes to doing this. Some say that it will drive off all of the CO2(I don't inject it) yet others, like some of the people in this thread, said that it will add some CO2 back to the water. What do I believe?

I do have an Aquaclear 20 in that tank but the flow has greatly been reduced since my betta does not like strong currents. The filter is only used for mechanical filtration as well as some circulation. Would it be a bad thing to add a small bubble wand to the tank along with keeping the filter in there too? I would definitely use a flow regulator to control the amount of air that goes into the wand.

The filter is on the opposite side of the tank and the heater is on the other. I wanted to put the wand near the heater to help distribute the heat around better. The reduced flow from the filter doesn't spread the heat around as good as it would if I didn't have sponge on the inside and end of the intake tube.

 

Having the flow restricted on your filter will lower the O2 levels in your water because the surface isn't being disturbed. It doesn't make much difference to the betta (they breathe mostly from the surface) if the O2 in the water is a little low, I do not know anything about snails, so I can't say if they are effected by low O2. This would be the primary technical argument for adding a bubble wand. It is the process of disturbing the surface of the water that allows O2 to enter the water (and some waste gases to escape).

As far as heat distribution goes I would not worry about it in a 10 gallon tank it is too small of a body of water to have significant differences from one side to the other. although I would recommend upgrading your heater if you have a cheap one. I followed the advise in this forum and bought Stealth heaters for both my tanks and they keep my tanks within a constant 1.5 degree range. Basically they are set and forget.

Don't worry about the CO2 factor, any effect on a non CO2-injected tank is insignificant.

Bubbles can be pretty, and bettas sometime like to play with them. Although I had a betta who was intimidated by the bubbles, even going slow, and I had to remove them. Then again air pumps and another piece more equipment to your tank with air lines to hide. I think in my humble opinion that these last aesthetic reasons should be your determining factor.

 

Thank you for this information.

Adding a little O2 for my betta wasn't really a concern but it is my snails that I wanted to add the wand in there for. They do much better with some added O2 in the water, especially nerites.

As for hiding tubing, it doesn't really matter to me since both of my tanks are in my bedroom and it's mainly me that sees them on a daily basis.

I use the Hagen MinI submersible heater(50 watts) in my 10 gallon and I have never had any problems with it. I would like to get either the Stealth or Theo Hydor heaters for both of my tanks and use the Hagen ones as back ups in case I ever need them.

 

If you are concerned about the saturation of the o2 in your tank take the water and check it for the disovled o2 in the water, then you know exactly what you are dealing with.
Its obvious that having o2 in a tank at high levels can't be a huge problem. Look at the species they have found in Antartica in the high o2 level waters, they have giant crabs, giant species never seen before.... Then there were a lot of studies out there about the Pacific ocean from the warming trends where the disolved o2 was down and that was killing out the fish species, reefs, etc. That in itself says you need o2.....

Being a resp therapist... O2 is good! low o2 is bad... goes w/ people and all types of living beings....

Not only that the only concern w/ high levels of disovled Oa2.. I would only worry about alage growth...

BTW in my 10 gallon planted tank I use a very small pump and very small air stone, my plants grow wonderfully and my fish are healthy.... (I will post picks of that tank I really need to, I am so proud of my plants its the only thing I have a green thumb w/ aquatic plants lol)

 

I thought that too much CO2 is one of the causes of an algae outbreak, not oxygen.

It's good to know that your tank is doing well with an airstone in it. Is your pump a submersible pump to circulate the water around or are you referring to an air pump? I'd certainly love to see some pics of it!

 

I thought that too much CO2 is one of the causes of an algae outbreak, not oxygen.

It's good to know that your tank is doing well with an airstone in it. Is your pump a submersible pump to circulate the water around or are you referring to an air pump? I'd certainly love to see some pics of it!

This is according to my husbands knowledge of water... (he has a bachlors in enviromental science) it does make sense w/ the alge being a living thing the o2 would aid its growth... along w/ light. My pump is just a reg cheap air pump from walmart not submersible.. then I have my reg filter. I will post a pic tomm.

 

O2 should not cause more algae. And no, you can't have too much aeration. The bubbles breaking the surface of the water are generally a good thing. The only ones who worry about it are those injecting CO2.