CO2 resistant fish?

[Jose]

Hi everyone,

Has anyone had most of their fish gassed with co2 and had maybe just one species survive? Im really interested in finding what fish are most tolerant to co2.

Are gouramis, bettas etc actually more resistant to high co2 levels. What are your experiences?

In my experience Amber tetras are a good example of these. Any Ideas?

 

[Julian]

Nuked my tank once. SAE and tetras died, Ottos survived - they were all sucking on to the side of the glass and had their heads poking out of the water which probably helped.

 

[dw1305]

Hi all,

Are gouramis, bettas etc actually more resistant to high co2 levels. What are your experiences?

I don't have any practical experience, but they definitely should be more tolerant of high CO2/low O2. If fish gulp air (like Corydoras catfish) that would also allow them to survive for longer at low oxygen levels.

You would really need to know where the sites of gas exchange are, if CO2 only diffuses out through the gills, then high levels of CO2 in the water would be toxic whatever happens. there are details in <"THE EFFECTS OF OXYGEN SATURATION AND CARBON DIOXIDE...">.

In my experience Ember tetras are a good example of these. Any Ideas?

It would definitely be a small fish (due to to the size volume ratio) and one from still, warm water with a lot of organic matter. It may also be fairly sluggish.

I've got a reference some-where that lists the "Root effect" for haemoglobin in various Amazon basin fish, and I think some characins were recorded which had no Root effect.

cheers Darrel

 

[EnderUK]

Pentazona-Barbs seem quite bullet proof and when I screw up my CO2 they are still usually quite happily swimming around the bottom while my rainbows, mollies, gourami, ottos and SEA start gasping at the surface. If I pushed it too high then they usually start to huddle around the filter intake rather then the surface. I think ottos are really just better at shutting down then other fish when CO2 climbs, they cling to something and preserve energy, probably doesn't mean they are happy.

 

[Christos Ioannou]

...been there done that. All of the Pink zebra danio survived. While not a fish, one of the survivors was an Amano shrimp!
Some fish did jump out of the (open top) tank.
Fatalities included cardinal tetras and rummy noses.

 

[Rahms]

bettas should be able to take high CO2 because of their labyrinth... system/organ (not sure what to call it). But if you're asking about CO2 tolerance that tells me you plan on injecting a lot, so you'd want good flow to actually distribute it.... My understanding is that bettas don't do too well in high flow due to their fins being so large, so I'm not sure they'd be a great choice! Maybe female bettas are stronger swimmers

 

[Jose]

bettas should be able to take high CO2 because of their labyrinth... system/organ (not sure what to call it). But if you're asking about CO2 tolerance that tells me you plan on injecting a lot, so you'd want good flow to actually distribute it.... My understanding is that bettas don't do too well in high flow due to their fins being so large, so I'm not sure they'd be a great choice! Maybe female bettas are stronger swimmers

Yes this has also crossed my mind. Thats why you normally see small schooling fish in high techs. And not a bunch of female bettas I guess.