New DIY CO2 reactor, fish gulping air??

[Chicago_Cheech]

I had not done anything with CO2 until today. I did the DIY 2 litre bottle method and put the outlet line into the intake of my Magnum 350 canister. All has been working well and I've seen some bubbles and heard some gurgling in the filter. None of the CO2 is bubbling directly to the surface. All is going through the canister filter.

Nowmost of my fish are all up top, appearing to be sucking air off the surface. Did I do something wrong?

-Cheech

[reiverix]

I guess you could check your pH and KH to calculate your CO2 level. It's unlikely you will overdose CO2 with DIY on a 55 gallon. Also check that none of the mix is getting into the tank. The first time I used CO2 I also put the line into the filter intake but the gurgling sounds made me too nervous. I'm sure there's many who will disagree but I don't believe cannisters are equipped to deal with CO2. Fluvals anyway.

[tmorr37]

same thing happen to me I think they were out of oxygen. so I got rid of it. I had mine just hooked up to an airstone

[tamccain]

I had my CO2 hooked up quickly after just adding my first plants. I think I ended up adding more CO2 than what my plants needed because my fish were breathing heavy and hovering near the top. I looked some things up and it seemed that there was a lack of O2 due to the CO2. After I changed the setup so that less CO2 was being absorbed and my fish recovered.

[Walker_]

I had a similar thing happen with a 45 hex, however I did nothing and after a few more hours I found ALL my fish floating upside down at the top of my tank..... however I could still see them slowly breathing. I disconected the C02 and ran an airpump and within 45 min they were fine.... My guess is you have too much C02 going in.
note: I have heard of something called Carbonic Acid that is suposed to be produced when running C02, this may also be the problem. however I am in no way an expert on this and someone with a little better understanding of water chemistry may have a better idea...
-pat

[reiverix]

There's plenty people on here, myself included, that pump CO2 to ~30ppm and have no fish gasping at the top, even with minumum surface agitation. Also, CO2 and O2 levels are not related. Your water can be high in both. Injecting CO2 into a tank does not drive out the oxygen.

Maybe it could be down to overstocking or not enough plants to warrant CO2 injection.

[tuchon35]

I have Co2 levels around 35ppm and the fish are doing fine. What do you use for a buffer? It might not be the Co2 levels but the PH. I have my tube going into a magnum 350, it does gurgle a little bit, but i can't hear it when the stand doors are closed. I have never had a problem with the filter malfunctioning. You should measure all of your levels and see if it is something else.
There might be some good in the situation, If it is your PH, just put some crushed coral in your filter instead of carbon. Also, you know your Co2 is getting disolved into the water column, if it is bringing down your PH.

[Chicago_Cheech]

pH came down, but not dramatically. What I DO know it that once the CO2 line was removed, all fish improved and were back to normal within an hour. I think my reactor was putting out waaaay too much gas. I will do another batch this weekend and let the CO2 production slow down before putting it in the tank.

Thanks

-Cheech

[Jason01]

What did you use for a mix, and how much of what?

I have been using DIY for several months now, and have had levels in the high 20's, and never a problem with any fish gasping at the surface.

You also never posted what your KH/PH readings were. There is no accurate way for us to help you if we don't know what the readings are! We can guess, but that isn't always the best way to go about things.

[jonathan03]

It might not be the CO2, but if any of the alcohol from the yeast bottle gets into the tank it can be very bad. It can definately kill your fish if there is too much of it. Smell the water for signs of an alcohol smell. If you smell alcohol, do a water change as soon as possible.

Sometimes the reactor creates a siphon and pulls some of the liquid from the tank back into it or vice versa. Definately be sure your using a good check valve. The liquid in the CO2 reactor is very poisionous to the fish and plants, but the Co2 it makes is beneficial.

[Bayesoft]

Walker,

Carbon Dioxide is not an inert gas. It leans towards acidic, producing Carbonic Acid when dissolved in water.

Carbonic Acid lowers ph by neutralizing alkalines.

Go here to learn how Carbonic Acid decomposes in water;

http://www.newton.dep.anl.gov/askasci/chem99/chem99661.htm

[Jay]

There is a lot of speculation going on here without any facts. Guessing is going to get you into more trouble. What are your numbers both before and after the problem?

GH?
KH?
Ph?
NH3
N02
NO3
Temp

I could guess too and say that it sounds like a Ph crash but that is not helping you.

[Swimfins]

Its hard to figure that one co2 diy 2 litre can cause gasping fish. I have 5 x 2 litre on my 66g. Ph is 6.8 as of this morning. KH is 3.9 dh. I am pumping about 19 ppm . Fish are fine. I have a 4 inch clear plastic spice bottle that I run my spray bar through, I feed the co2 line through the bottom of it the bottle. I tried feeding the line directly into my canister filter, however, I couldn't get the co2 level higher than 10 ppm, because the co2 was not staying in the water long enough to affect the ph.

The situation described above sounds strange. I would not suspect your co2 system as the culprit. Perhaps amonia, nitrite, and nitrates?

[Chicago_Cheech]

Guys, I don't have the numbers but my DIY CO2 experiment is over. The water in the 55g tank has always been rock solid stable. When I put the CO2 in, the fish gasped. When I removed it they did not. That is enough for me. Thanks for the commentary.

If I approach this again, I'll get before and after measurement of everything.

-Cheech

[Harlock]

Wow, I had DIY CO2 on a 29 gallon and everything went well. Er, I know you neglected to d any testing of the water, but could you tell us what you put in the DIY mix itself? I mean to ask, what recipe did you use?

[Chicago_Cheech]

2 litre bottle about 2/3 full of water, approx 2 cups of sugar and a half tsp or so of bread yeast. Mix was bubbling vigorously within an hour. I fed the cO2 bubbles into the intake of the canister filter.