Big Gigantic tank crash!!!! Help please.

[hulkamaniac]

So I get up this afternoon (I work third) and go to feed the fish. My 75g tank in my living room has completely crashed. I suspect it's because of the pressurized CO2 I've got on it. For some reason it went out of control and the filter is spitting out huge bubbles of CO2. Also, every single fish in the tank (no exceptions) is floating on the surface. I added a powerhead and re-adjusted the filter outflow to provide more water movement. I think I'm going to do a water change with some more oxygenated water. Some of the fish look like they're starting to recover, but I'm afraid some of them (like my BN pleco) may be too far gone. Is there anything else I should consider doing.

I tested the water. The PH had crashed to 6.0. Ammonia and Nitrite were both 0. Also, I turned the CO2 off for now.

 

[SparKy697]

I had a similar thing happen just a couple of days ago. I shut the co2 off and increased surface movement. The next morning everybody looked like they were back to normal.

You have done just about everything I can think of at this time, other than an air pump/stone. All you can do now is wait and see.

 

[hulkamaniac]

After doing the water change I seem to have woken up the Upside down cat (survivor of my one other tank crash). The BN pleco continues to lie there and I'm afraid he's a goner. Most of the other fish seem to be stirring though they're still belly up on the surface. Some are swimming awkwardly in the mid-level.

 

[7Enigma]

One of the most important things to do is to make sure the surface is uncovered. I'd go as far as to remove the top or at least keep the glass top open. I'd also get a fan and have it blowing across the surface. CO2 poisoning is no joke, and you want to get it out of the water ASAP! I know this doesn't help the OP in particular (since it already happened) but for future problems try to get the water agitated quickly.

Remember in a CO2 poisoning its NOT oxygenation of the water that helps the fish, but rather getting rid of the CO2 from the water that is the difference between life and death.

 

[hulkamaniac]

Well, today the fish seem a little lethargic, but otherwise everyone is ok. No one appears to be permanently injured. I'm a little reluctant to turn the CO2 back on now.

 

[7Enigma]

What is your regulator's pressure? If its under 500-600psi I think that would be the cause. If its still high check to make sure your needle/lpr wasn't bumped/damaged. It sounds like a tank related issue to me so start from the tank itself and follow the gas.