airstones vs co2

[focus]

ok i need help been given a lot of diffent info by lfs
i have real plants not doing as well as they could been told to try a co2unit
BUT do i have to take out my airstone to help the co2 work proberly

 

[Alien Anna]

As I told you, I put an air-stone in when I got CO2. The reason you're being told not to is simply that if you haven't got a good diffuser and you generate too much surface disruption, the CO2 will be expelled before it can dissolve.

OTOH, at night when plants are using oxygen and producing CO2 the oxygen levels in the tank could theoretically go down, so an air-stone may be helpful.

 

[AquaNut]

As Alien Anna said, you should run an airstone at night if you're using CO2. I wouldn't run it during the day. The more gas exchange you create at the surface of the water, the more of the CO2 you're creating that's disappearing into the air.

 

[rosierabbit]

OTOH, at night when plants are using oxygen and producing CO2 the oxygen levels in the tank could theoretically go down, so an air-stone may be helpful.

don't the plants use CO2 and produce oxygen

 

[AquaNut]

OTOH, at night when plants are using oxygen and producing CO2 the oxygen levels in the tank could theoretically go down, so an air-stone may be helpful.

don't the plants use CO2 and produce oxygen

During the day, yes. At night, the process is reversed.

 

[rosierabbit]

wow, i never knew that do all plants do that? stupid me never concentrates at school

 

[allnatural]

Yes. Land and aquatic plants "respirate" at night. Basically plants produce CO2 24 hours a day. When it is light, the plant cells will also produce oxygen through photosynthesis using up the CO2. At night, the process is really not reversed. What happens is that at night, the plants stop producing oxygen so your fish are using up the available oxygen in the tank. If you have enough plants, and a respectable number of fish, there will be enough oxygen left over until the next day.

It is an interesting relationship. If too much CO2 escapes, or there is not enough of a dark period, then plants will "suffocate". If there is not enough oxygen produced by the plants, the fish "suffocate".

--Tim

 

[AquaNut]

Lol My bad. I really should avoid scientific issues. I was a history major, after all.

 

[Alien Anna]

Yes. Land and aquatic plants "respirate" at night. Basically plants produce CO2 24 hours a day. When it is light, the plant cells will also produce oxygen through photosynthesis using up the CO2. At night, the process is really not reversed. What happens is that at night, the plants stop producing oxygen so your fish are using up the available oxygen in the tank. If you have enough plants, and a respectable number of fish, there will be enough oxygen left over until the next day.

It is an interesting relationship. If too much CO2 escapes, or there is not enough of a dark period, then plants will "suffocate". If there is not enough oxygen produced by the plants, the fish "suffocate".

--Tim

This might be an additional reason why I lost fish when on holiday - I'd forgotten that in the dark, plants use oxygen. If you remember, my neighbour had a problem with the lights and my tank was in darkness for 11 days.

 

[allnatural]

If anyone has read this post, I have edited it.... I was wrong

Well, I have done some research.. According to Diana Walsted's "Ecology of the Planted Aquarium" plants DO use oxygen, put they store it in special cells during photosynthesis. They prefer to get the oxygen from these cells instead of from the water. So I suppose if the oxygen in these special cells were depleted, then they would have to use it from the water. All things being equal though, plants do not use sigificant amounts of oxygen like animals (fish) do.

Sorry for my bad information.

--Tim

 

[allnatural]

OK, poor focus, we always get a little off the subject. How much are they going to charge you for this CO2 system?

As Alien Anna said in a round-about way. She ADDED and airstone when she got the CO2 injection. I am not sure why she did that, it doesn't seem logical to me, but I don't use CO2 injection. You are going through all this work to add CO2, then letting it escape. Boggles the mind

There are MANY reasons why plants may or may not do well. A lack of CO2 is certainly one of them. You have to also look at your lighting, how long you leave the lights on, the substrate the plants are planted in, etc... You should not be using an airstone if you want plants. Plain and simple. When the bubbles pop at the surface some of the CO2 that is in your tank escapes.

What I would try before getting into the CO2 stuff is to remove the airstone. If you want water movement and/or a filter, use an outside filter like an Aqua Clear, or an internal cannister filter like a Fluval. If you use the Aqua Clear, don't run it at full speed. Do not use charcoal or a filter cartridge that contains charcoal.

--Tim

 

[focus]

thanks for the post guys the thing now is iv'e taken the airstone out but after maybe 3 to 4 hours the fish are top of the tank gasping again
i no this couldn't be lack of oxygen and i not my nitrite is a little tank doing a mini cycle.
my fillter is surpose to add oxygen to the water but i don't think it adds that much
put a co2 in there yesterday only cost £8 i'll give it a go tillit runs out then i can put my airstone back

 

[Alien Anna]

As Alien Anna said in a round-about way. She ADDED and airstone when she got the CO2 injection. I am not sure why she did that, it doesn't seem logical to me, but I don't use CO2 injection. You are going through all this work to add CO2, then letting it escape. Boggles the mind

It only boggles your imagination because I didn't tell you everything!

The tank is a moderate sized Juwel tank with an in-built Juwel filter. Juwel's are great at biological filtration, but not good at aerating the water. My tank is unhealthily hot most of the time (84F is not unusual) which obviously reduces oxygenation. So, to boost the aeration of the tank I installed an air-stone by the Juwel pump out-let. It just causes a little more turbulence and ensures the water is oxygenated.

At the other end of the tank, the still bit where my gouramis hang out, I installed the diffuser for my CO2 system. The diffuser is like a marble run for bubbles that you stick on the side. Because of the way it works, the CO2 is in contact with the water for a fairly long time and therefore dissolves quite well. This means that surface disruption is unlikely to cause loss of CO2 - that is only an issue if you are using something like an air-stone for CO2 dispersion and need to hold the bubbles under the water for some time. Dissolved CO2 tends to stay in the water far more easily than small bubbles of CO2 gas.

 

[focus]

thats what i got the little bubble run r they any good dose it work well?
i find my self look at the co2 unit watching the bubles

 

[Alien Anna]

thats what i got the little bubble run r they any good dose it work well?
i find my self look at the co2 unit watching the bubles

I've only had it a week but so far it's working great - I've got a nice load of bubbles on the underside of my plants and already I'm getting stronger plant growth. My only problem to date has been on of my tetra's fascination with the diffuser - he got stuck in it!