I have a 55 gallon tank that has been running for a little over a year now and Have about 12 fish in it, all cichlids. I was doing my weekend cleaning and adding two new powerhead and ugj's and forgot to plug my air pump back in and a couple of hours later all my fish were either up top like they were gulping for air or swimming around and gasping for air. I pluged it back in a within hours they returned normal. None of my other tanks has this problem and don't have any air stones or extra air pumpint into it, so what could cause this???? Is this normal for Cichlids or are they just used to have extra air being pumped in????