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CO2 ran out, fish super active!

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PM

PM

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My co2 ran out a couple of days ago and I’ve noticed my fish (community tank) are all super active and occupying all areas of the tank, which I have never seen before. All of them have been in there for about 2 years.

Anyone else noticed this behaviour before?

It’s so much better! But I need to put on another cylinder before my algae goes wild.
 
I think this is more common than most high energy tank keepers would admit. Ive seen so many injected tanks where fish are static or limited movement compared to when a water change has just been completed. A lot photos and videos of injected tanks are also taken outside of the lighting/co2 period or after water change because of this.

That said, i have seen beautiful high energy tanks, particularly by @taistrietman, where the fish act like a low tech so its very achievable, just more difficult and requires a high degree of observation! (or a ph controller 😉)
 
Most local fish stores.... don't add CO2, fish are all active due to high aeration and regular water changes!
That's why we must be mega careful when adding new fish into a high-energy C02 Aquarium.
 
Hi all,
This was why I stopped using co2. I'm totally sure fish can be perfectly happy in co2 injected tanks as I know people who breed fish with co2 injection but whenever I've used it the fish seemed stressed.
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I'm not a CO2 user <"Are co2 enriched tanks really fair on the critters?">. I never will be, but if I was? I'd dial the CO2 addition <"down to ~15 ppm">.
Has anyone combined a tank oxydator with co2? would that even work or would the oxygen just force out the co2 and vice versa?
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I'll need to find a reference, but I'm pretty sure that they are largely independent. As I said I don't have any practical experience of adding CO2, but this was what @plantbrain (Tom Barr) said in 2011 <"Oxygen in a planted tank."> and Clive (@ceg4048 ) in 2014 <"CO2 stability, brush algae and EI water change">. I think they have probably pushed the CO2 level higher than most other people

Fish will differ in their response to raised CO2 levels via the <"Bohr and Root effects">.

I don't actually think you need an oxydator <"Söchting Oxydator">, anyone who has plants that are actively pearling, while the CO2 is still on, will have water that is saturated with dissolved oxygen and with ~30 ppm CO2.

cheers Darrel
 
Has anyone combined a tank oxydator with co2? would that even work or would the oxygen just force out the co2 and vice versa?
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I’m not sure what an oxidator is but I run CO2 and an air pump simultaneously. My fish are always active and swimming around.

dw1305 said:
I'm not a CO2 user <"Are co2 enriched tanks really fair on the critters?">. I never will be, but if I was? I'd dial the CO2 addition <"down to ~15 ppm">.
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That’s pretty much what I do. I don’t know what ppm I’m at exactly but the drop checker is just green. It’s certainly not as aggressive as some would go for. Invertebrates don’t do as well in there though and shells do tend to soften/break easily so it’s clearly acidic.
 
PM said:
Anyone else noticed this behaviour before?
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Yes, I have - a definite increase in fish activity when CO2, previously ran at 30ppm, was switched off.

I’ve also done this:

dw1305 said:
I never will be, but if I was? I'd dial the CO2 addition <"down to ~15 ppm">.
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. . . and it was much better.

You certainly have to be more careful if balancing the light levels to suit, and plant selection might be more critical, but the fish were certainly a lot more active.
 
Wookii said:
You certainly have to be more careful if balancing the light levels to suit, and plant selection might be more critical, but the fish were certainly a lot more active.
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dw1305 said:
I'm not a CO2 user <"Are co2 enriched tanks really fair on the critters?">. I never will be, but if I was? I'd dial the CO2 addition <"down to ~15 ppm">.
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I have just started my entry into CO2 injection and have made an active decision to aim for 15-20PPM and plants that suit.

I just noticed too much change in (my) fish pumping in 25-30PPM.
 
Bradders said:
I have just started my entry into CO2 injection and have made an active decision to aim for 15-20PPM and plants that suit.

I just noticed too much change in (my) fish pumping in 25-30PPM.
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I didn’t notice much growth difference with more co2 than “some” co2 either. I think 15-20 works quite well if you have a relaxed-gardener approach.
 
Has anyone combined a tank oxydator with co2? would that even work or would the oxygen just force out the co2 and vice versa?
Click to expand...
I did this. The oxydator is a neat, simple little device, and it definitely put out a steady stream of O2, but I didn't notice any great effect on my plants or livestock and ended up getting tired of replacing the H202 and scrapped it. Without a DO meter, I was unable to confirm an increase in oxygen in the tank, but I assume it helped somewhat. My understanding regarding CO2 and O is the same as dw1305's -- dissolved oxygen does not displace dissolved CO2 in the water column, rather they are independent. It may seem that CO2 reduces oxygen due to two phenomena, i.e. that excessive CO2 makes it difficult for fish to breathe and an airstone will reduce the amount of CO2 in a tank, but neither is due to the dissolved oxygen displacing dissolved CO2 in the water column, but rather they are due to how fish breathe and the increase in gaseous exchange at the surface caused by the airstone.
 
As a point of interest, several Shrimp breeders I’ve read about seem to think Oxydators are beneficial in their tanks.
 
I wonder if you had an oxydator or oxydators working well enough whether you could achieve pearling from plants without co2 by achieving oxygen saturation without an airstone or something creating a lot of visible bubbles.
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Pearling is possible without CO2 or any extra equipment if conditions are right! I typically see it every day in my higher light tank. Some plants are more prone to it than others, and while I always consider it a good sign, you can have a perfectly happy tank that never does it.
 
Hi all,
ElleDee said:
Pearling is possible without CO2 or any extra equipment if conditions are right! I typically see it every day in my higher light tank. Some plants are more prone to it than others, and while I always consider it a good sign, you can have a perfectly happy tank that never does it.
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You are right, a lot depends on the conditions, and even <"very eutrophic water"> can feature pearling in the <"right circumstances">.

Cheers Darrel
 
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