Air pump

[jd67]

Would an Air Pump along with my Fluval 204 Filter put more oxygen into tank

[MatsP]

Yes, an airpump will help putting oxygen in the water. However, the main part of putting more air in the water is actually through the fact that the air-stone causes water from the lower regions of the tank to be moved to the top of the tank, thus causing more water to come in contact with the air at the top of the tank. Some years ago we did a quick virtual back-of-a-fag-packet calculation, and came to the conclusion that the contact with the bubbles in the tank is 1000x [give or take a zero] less than the surface contact at the top of the tank.

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Mats

[jd67]

If I keep the outlet hose from filter out of water instead of submerged would that do the same job

[MatsP]

If I keep the outlet hose from filter out of water instead of submerged would that do the same job

That's certainly not a bad idea, as long as the noise isn't too bad. But it's not lifting a large volume of water from the bottom to the top - even if the intake of the filter is that the bottom, it has much less effect than an airpump.

I'm not sure what you are trying to achieve, so I'm not sure what to recommend as the right solution. I take it this is to do with your H. wyckii and black shark - in which case I suspect oxygen levels in the water may not be the critical factor. Ammonia and nitrite levels would have to be checked first, as both of these also affect the fish's ability to breathe (or technically, in the case of nitrite, the ability of the blood to absorb/transport oxygen - a bit like Carbonmonoxide for mammals [in fact, nitrous oxide of the right form has the same effect on humans as nitrite does on fish, because it forms nitrite in contact with blood, and stops the hemoglobin from doing it's job]).

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Mats

[jd67]

I cleaned filter and fish are looking better. If I find that Ammonia and nitrite levels are high what is the best way to deal with them.

[MatsP]

I cleaned filter and fish are looking better. If I find that Ammonia and nitrite levels are high what is the best way to deal with them.

Any level above "zero" the ammonia and nitrite are toxic to fish, and if the fish are showing any sign of distress (gasping for example), the only practical solution is to do large water changes (50% or so).

--
Mats

[jd67]

Sorry to be a nuicance but I am new to this. Would this be okay to test water API 5 in 1 AQUARIUM TEST STRIPS X 25 STRIPS F&SW or this? API Freshwater Master Test Kit.

[MatsP]

The paper strip types tests are good to get an idea that something is absolutely and terribly wrong, but the drip tests are (when correctly used!) a lot more precise [they are still not VERY precise, but they are much better than the paper strips].

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Mats

[jd67]

Thank you for all your help

[Shane]

You may find the below interesting.

http://www.planetcatfish.com/shanesworl ... ved+oxygen

-Shane

[jd67]

Shane,thank you very interesting.

[Farid]

jd67,
if you keep catfishes in this tank ...surface movement for sure is good. but i would still use a airpump as insurance if anything with the filter should go wrong (as the cats ar not really the cheapest fish to get) once my eheim professional III was quite blocked so the outlet wasn't strong enough anymore to get enough water movement on the surface...all my adult L200 were under the surface to reach for air...since then i also use an airpump on this tank! all other tanks are airfiltered. which i would say is the best solution for a high-temperature catfishtank...

farid

[andywoolloo]

farid,

what do you mean airfiltered?

I have been seeing some air things at the fish store that look like an internal filter but shoot air out with a top thing like a sprinkler head that goes back and forth. Is that what you mean?

I 'll try and find a link to them.

[jd67]

QUIET AQUARIUM AIR PUMP FOR 50 - 400L FISH TANK SILENT Would this be suitable £10.99

[MatsP]

farid,

what do you mean airfiltered?

I have been seeing some air things at the fish store that look like an internal filter but shoot air out with a top thing like a sprinkler head that goes back and forth. Is that what you mean?

I 'll try and find a link to them.

I think "airfiltered" in this case means an airdriven sponge filter (or something workiing along the same principle: Using air to pull water through a sponge. Farid has posted several DIY solutions following this pattern.


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Mats

[Farid]

exactly as Mats writes

[sampster5000]

I have some questions. What exactly is happening to the water when you raise the temperature and why do you need to increase aeration? By this I mean why do we need more air stones? Also, when you add powerheads or have your water level down a little so they drip, what is happening? How does this increase the amount of oxygen in the tank? Where does the oxygen come from? How does moving water create oxygen? A little confused. I read Shanes article on oxygen in the tank and learned a lot but also became even more confused with the great amount of information.

[MatsP]

What we are talking about is "dissolved oxygen", that is oxygen IN the water.

Let's now start with a bit of an analogy. Have you tried opening a can of fizzy drink when it's warm? Does it bubble more than when it's cold? It does. That's because the gas which makes the fizzy drink actually fizz is dissolved in the water.

So, equally, when we dissolve oxygen in water, it "fizzes off" quicker when the water is warmer.

In a can of fizzy drink, the fizz comes from pressurized gas. With fish tanks, we have to rely on the water's ability to absorb oxygen. This happens at the water-surface. So, by circulating the water in the tank, we get more water in touch with the air.

And air-stones do supply a little bit of air (oxygen) into the water, but more importantly, it circulates the air from the bottom of the tank to the surface, where it can get oxygenated.

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Mats

[sampster5000]

So are you saying the oxygen leaves the water quicker when it is warmer and that is why we need more movement of water to the surface? Or does the oxygen dissolve into the water quicker when its warmer? But that wouldnt make much sense. Also, what is the heat actually doing? Speeding up the oxygen particles making them dissolve quicker?

[Suckermouth]

Oxygen (and gases overall) are less soluble in warm water. This is because the gases become more "active" and bounce around more, allowing the water to hold it less. Let's say you have two aquaria that are exactly the same, except one has cold water and one has warm. The warm water will hold less dissolved oxygen.

If oxygen levels gets too low, fish start running out of oxygen and of course bad things start happening. If the water is warm, then the water holds less oxygen. Thus, there is less oxygen for the fish. The fish will use up the oxygen in the warm water up in shorter time in the warm water than in cooler water, not only due to their being less of it, but fish also use oxygen faster in warmer water.

As mentioned, water will absorb oxygen at the surface. What will happen is that all the water at the surface will absorb oxygen until it becomes saturated, and then it stops absorbing oxygen. This will occur even if lower levels are not saturated with oxygen. Yes, oxygen would slowly and passively diffuse through the water to lower levels, but fish and other things are all using oxygen in these lower levels, so diffusion alone may not be enough. The fish will use up oxygen faster than it can be brought into the water. You might see fish go to the surface for oxygen in these cases.

To combat this, we increase flow. This allows mixing of the deoxygenated water in lower levels of the tank with the more oxygenated surface water. First of all, this allows oxygen to get down to lower levels faster from the surface. Also, it prevents the surface from being totally saturated and then not also carrying the oxygen back down, because it is being replaced by deoxygenated water that can then absorb more oxygen.

At least, this is as I understand it.

[Bas Pels]

As written above, warm water does not dissolve gasses as good as cold water does because gas molecules go further away from each other, just as what happens without the water

Further, the fish do need more oxygen, because, as cold blooded creatures, their metabolism goes faster in warmer water.

This second observation obviously makes matters worse, but to top things off, the higher metabolism also pollutes the water faster. Polluted water is less able to contain oxygen (don't ask me why) and part of the oxygen in the water is needed to oxidize the pollution

Therefore, when the temperature in the tank gets too high, waterchanges with cold water are very effective: they cool the water, but they also reduce the pollution of the water, making the possible oxygen content both higher and better available

Air pumps only help in getting the oxygen content of the water closer to the possible value. Usefull, but sometimes not enough

[Suckermouth]

Polluted water is less able to contain oxygen (don't ask me why) and part of the oxygen in the water is needed to oxidize the pollution

Decomposers use oxygen to break down their "food" just like fish, so if there's a lot of waste being broken down then more oxygen will be used.

[Bas Pels]

No, I'm referring to something else.

I have a pH measurer, which also measures redox potential. For those who faced chemistry only in school, redos is reduction / oxidizing, and the redox potential gives a measure of the oxidizing potential of the water

If I take a cup of water from the tap, the redox potential is 150 mv. if I put in some sugar, it gets lower

I have faced tanks in which the fish did not respond to waterchanges, or responded very slowly. measuring the redox potential told met the water had, still, a very low potential. Looking for a reason, I always found something rotten - a dead fish, some bad wood, whatever

This system - organic matter reduce the redox potential of the water - make problems very bad indeed: getting rid of them costs oxygen, but even if not gotten rid of, the oxygen is not as usefull as before

[sampster5000]

Thanks for the answers. I understand it all. I guess I would understand it more if I had paid attention in chemistry and biology! I wish I could see a formula showing water grabbing oxygen out of the air. That would actually make a lot more sense to me. Im glad I know more about water temperature and the effect of it. I never felt good about high water temperatures and now I can see why!

[MatsP]

Well, why didn't you ask that in the first place. Scroll down a bit on this page, it will show you the formula(s) needed to calculate the saturation level of water at various temperatures:
http://waterontheweb.org/under/waterquality/oxygen.html

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Mats

[sampster5000]

Sweet thank you!

[apistomaster]

The dissolved O2 level at a given temperature and the ReDox Potential of water are two different but not totally unrelated things.
The maximum dissolved oxygen level of water is very dependent on the water temperature.
A high ReDox Potential is generally a desirable condition but it is not a measure of the dissolved oxygen that is available to the fish for respiration. It defines how potentially reactive the water is chemically with other substances as I understand it.
These are fairly complicated subjects.
It is best to make sure you do regular water changes, supply some kind of airlift driven filter and/or air stone in addition to any power filter you use and you should not have any problems.

[Bas Pels]

A high ReDox Potential is generally a desirable condition but it is not a measure of the dissolved oxygen that is available to the fish for respiration. It defines how potentially reactive the water is chemically with other substances as I understand it.

That is completely right

I'm a chemist, thus i know what redox potential is (for instance, iron can oxidize in a medium with a certain, raletively high potential, zinc, less noble, needs less) and therefore I can not explain WHY a low redox potential is harmfull to the fish (after all, they take the same oxygen out of the water) but still, it is.

knowledge from chemistry sometimes helps, but my fishes don't life in a test-tube - that is, I know the system in a tank is so much more complex, that simple chemisty often does not apply - you have to translate it, more or less

[apistomaster]

A low redox potential in aquarium water is often associated with organic decay. The relationship between low redox potential and low dissolved O2(DO) is intertwined and the reverse is true. Decaying organic matter loses dissolved oxygen directly from the respiring nitrifying bacteria but the the decay also involves separate chemical reactions with the water.
This is really an academic distinction that few aquarists consider although many advanced reef aquarium keepers can see how important both are to the health of their animals.
Plecos coming from rapids need both factors to be as high as possible for a given temperature for their optimal well being.
Altum Angels have proven to require both high DO levels and high redox potential to be at their best. In clean flowing streams both of these factors will be higher than what is usually measured in aquariums. It takes artificial methods like ozone injection or in a more round about way, very intense UV exposure to maintain a high redox potential in aquariums. Far more UV radiation than is typically used in aquarium water sterilizing units. Very high UV intensity creates ozone and ozone greatly increases water's redox potential.

[Farid]

you understud it very well!

how the oxygene gets into the water:

the more movement there is between water and air the more oxygen will be picked um by the water. look at is as friction between the two elements.

bubbles alone disolve not very well as long they are unter water...the surface is the biggest space where this friction can happen..so the more we move this surface the more friction will happen the more the water can be saturated with oxygen.

it not really the bubbles moving up in the tank...this move is to fast to really disolve enough...but it's the movement on the surface the bubbles cause....this is why a tank with a non moving surface (without an airpump) will have a lack of oxygen. soon as the pump moves the surface already just a bit the fishes will have less problems as friction is built up a bit already ;)

more of less like that. about the higher temperature ...i can just say read the above one two more times ;)

farid