May have nearly gassed my fish

[jamesb]

So following a conversation on what makes red plants red I thought I would try upping my co2 injection rate....... Apparently I took this too far as some or most of my fish started either going to the top for air or going extremely lethargic on the substrate. The Pakistani loaches seemed the worst effected and I don't know if they will bounce back . I have done a water change of about 25 litres moved all powerhead, spray bars and diffusers to create a much surface agitation as possible. My only concern is the lights have now gone out and I am concerned the co2 the plants excrete is going to make it worse. I know it would probably produce an algae outbreak but should I consider leaving lights on all night do the plants continue producing oxygen or am I taking it too far?

 

[Iain Sutherland]

youve done all the right things, now just wait and see. Ive always been surprised how well they bounce back after a gasing in the past.
I wouldnt chase red plants though, even the top scapers on here struggle to 'see red' i consider it an advanced area of the hobby.

 

[Antipofish]

Hi James. It sounds like you have only "slightly overdosed" if you get what I mean. Sadly, some people allow their CO2 levels to reach pretty much what you have described all the time ! So on the upside, I think your fish will bounce back ok. Remember to reset your CO2 lower. What you can do in future, is to up the surface agitation as well as the CO2. Whilst increased agitation does allow a bit more off gassing of CO2, it also increases the O2 saturation allowing for even more CO2 to be injected. I believe that if you get this right, the increase is disproportionate. That is to say you dont lose as much CO2 as the additional O2 allows you to add. The reason this works is that as well as higher CO2 in the tank there is also a lot more O2 for the fish. From reading several of his threads, this seems to be the approach that Tom Barr has found successful. He often has CO2 saturations of twice what we would normally aim for with no effect on his livestock. Good luck

 

[John S]

I think your Pakistani loaches will be OK. When this nearly happened to me the first indication that something was wrong was the Pakistani loach loosing its colour, the markings had almost gone. It quickly recovered after a water change.

 

[dw1305]

Hi all,

When this nearly happened to me the first indication that something was wrong was the Pakistani loach loosing its colour, the markings had almost gone

It is always the rheophilic fish like Loaches, Gobies and plecs that have the highest oxygen demand, so they suffer from hypercapnia first.

cheers Darrel