Fish gasping

[PeterGwee]

Using an airpump is a temporary solution for your fishes welfare if low O2 during the lights off period is a problem. Getting to the root of the problem which is lack of good plant growth should be the long term solution.

[eric_kclee]

Just to clear some doubt...

I turn on the O2 so small that it is equavalent to 1bps as in CO2 (by means of a restritive valve)

Earlier was much bigger o2, realise that it raise the PH (driving out CO2), then was switched to tiny bit(1bps), verified that PH remain at 6.6. So assume CO2 is still intact.

Question,
Does PH6.6 means I still have CO2 in the water ?
(without CO2 injection, water PH is measured as 7.0)

[bclee]

What is your KH? You need this to know whether you really indeed have enough CO2.

BC

[eric_kclee]

KH 5, PH 6.6

[bclee]

CO2 level looks fine.

What is the purpose for using the airpump? To get rid of the surface protein layer or to aerate the water?

BTW, you seemed to have a misconception about the function of the airpump. Airpump is not equal to O2 injection. Airpump just equilibrate the dissolved air with the atmosphere but agitating the water. It is not pumping air into the water. And it is also not like bubbling CO2. Airpump uses agitation as the mechanism to help air dissolve (or equilibrate) while bubbling CO2 is directly trying to dissolve CO2 bubbles into the water. (Which also means that bubbling air at 1bps will not make any difference.) O2 is below equilibrium level O2 from the atmosphere will dissolve into the water. The thing is... for planted tanks... the O2 level is usually above the equilibrium level due to photosynthesis. So when you use the airpump, the O2 level will equilibrate with the atmosphere... meaning O2 will escape from water into the atmosphere to reach the equilibrium level.

That is different from fish only tank. Fish, nitrification, decomposition will all use O2. There is no O2 source in the water... so O2 level is constantly below equilibrium. That's why we use the airpump to bring O2 level up the equilibrium level.

This is the reason that most planted tank keepers do not use airpumps.

BC

[eric_kclee]

BC,
understand what you mean...

When water is satuated with O2, Airpump will drive away O2 and equate it to ambient...right?

When water is deprive from O2 (due to unhealthy plant), then airpump will means bringing up the O2 level in water to the level of ambient...right?

I initially use airpump to assist my tank (was off-balance due to over-trimming), realise that it help to remove protein layer, and understand now that it doesn't seems to cause algae....then intend to use it again to remove protein layer.

I didn't know that airpump cannot satuated the water with O2, thought that air contain O2, dissolve more air into water means dissolved more o2 in water...just like co2 injection....Thanks for your explaanation.

[budak]

I think the air pump bubbles work by agitating the water surface, thus increasing the rate of gas interchange.... for planted tanks, since CO2 easily diffuses into the atmosphere, air pumps are thus not favoured. With mainly fish tanks, the agitation is supposed to increase increase the surface area for O2 diffusion into the water (one way of putting it i think).

For the protein layer, the agitation simply breaks its adhesive bonds. But why not use a surface skimmer attached to your filter inlet, or get a couple of small guppies instead? Work as well and with much less maintenance.

[A.Rashid]

wah... so many threads to read makes me confuse oredi...
so from what i undertstand now is, to lower the CO² injection to X bpm? 15 enuf(=1 bubble every 4 sec)? and i need to arragate the water with air pump during the lights r off?

[A.Rashid]

now i know where my problem lies... after carefully reading and understanding the threads replied... my problem lies on the lights as it has not enuf for photosysnthesis to take effect thus creating less O² from the plant and too much CO² injected.... ok will definately do adjustment....
OK thanks bros for all the help. indeed a lesson learnt.

so with proper light wattage of 3watt/gal will definately produce enuf O² to last for the whole nite in the tank for the fishes?

[vinz]

Rashid,

Not by themselves. To get plants photosynthesising well, you need sufficient lights, CO2 and fertiliser. The 2 easiest things to get right are the lights(3WPG) and CO2(20-30ppm). After that you have to get your fertilising right.

[geoffrey]

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On 8/26/2003 4:51:11 PM

Aquatic plants often use C4 biochemical pathway of photosynthesis instead of C3.

BC
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BC, is it confirmed that most aquatic plants are more efficient CO2 users? Where did you find this piece of information? Do you know if there are any CAM aquatic plants too.

[bclee]

I got the information from an article from College of Agriculture & Life Science, The University of Arizona.

Still reading up on the biochemistry in plants to verify this information...

BC

[Allen_1971]

you sure about that BC?

If possible pls provide the link.

[bclee]

Here: http://ag.arizona.edu/azaqua/aquapla...aptations.html

I am also reading other articles/papers about photosynthetic pathway diversity of aquatic plants to learn more about aquatic plants. Interesting to learn that aquatic plants differs significantly from terrestrial plants most of which are C3 plants.

BC

[geoffrey]

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On 8/27/2003 11:32:57 AM

I am also reading other articles/papers about photosynthetic pathway diversity of aquatic plants to learn more about aquatic plants. Interesting to learn that aquatic plants differs significantly from terrestrial plants most of which are C3 plants.

BC
----------------

Good link BC. Thanks.

In fact, there are over 8000 species of angiosperms that are C4. They are not prevailing only in aquatic plants.

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On 8/27/2003 10:19:40 AM

Still reading up on the biochemistry in plants to verify this information...

BC
----------------

You may have already found out that C4 is indeed a more efficient way to fix CO2 compared to C3. More interesting is this fixation (C3 and C4) is done independent of light, hence the dark reaction.

I am more interested to know if there are any CAM aquatic plants. I seriously doubt there are any as the physiological purpose is to conserve moisture which aquatic plants, growing along water-ways and submerged, are not denied.

[bclee]

Check this out: http://www.werc.usgs.gov/seki/pdfs/photosynthetic.pdf

BC

[geoffrey]

Thanks man!! I was wrong!! There are indeed CAM aquatic plants!!

Need to read on to find out whether some are available here. I am with the presumption that having some CAM plants in the tank is good, particularly when I am running 24/7 CO2. Hopefully, pH swing can be smaller... : )