Foggy Water, Dead Fish, and other weird occurances...

You have ammonia poisoning. That is why your fish are gasping for air at the top of the tank.

A few questions for you to answer before much else can be said:

1. How big of a tank are we talking? 10 gallon, 30? 55?
2. How many fish do you have, and how big? (not counting tails)
3. What kind of testing equipment do you have? If you have the tests for it, what are your numbers for ph, ammonia, nitrites, and nitrates?
4. Have you ever had a fish tank before or is this your first?

About the only thing I can tell you at this point is to do a 30% water change every day. This will cut down on ammonia, and maybe save the rest of your fish.

I would also advise that you probably overdid it with the fish to start off with. Most of us do what is called "fishless cycling", where you get the bacteria necessary to keeping your tank healthy before you introduce any livestock. A few of us still cycle using fish, and there is an article at the top of this forum that will tell you a little bit about what is happening. If you can, take at least some of the fish back to the store you got them from. If you can get credit for all of them, I would suggest going ahead with that and doing a fishless cycle, because you're much less likely to get disheartened by losing fish if there are none in the tank to kill off....

Come back with some numbers, and we'll see what else can be said...

Okay.

10 gallons, 8 or nine fish, at least half of which are goldies, I'm assuming...

Okay. Fair enough. Now let's get you a healthy tank.

#1: You're going to need some tests. Ammonia, nitrite, and nitrate. They're not dirt-cheap, but they last a very long time.

#2: Unfortunately, I was right about overdoing the fish. The best thing for you to do is call the store where you bought your fish and ask if you can bring a few back. My advice is keep EITHER 3 or 4 danios OR 1 goldfish to start with. The better choice is the danios, since they will be able to stay in the tank forever, and the goldfish will outgrow the tank in a matter of months (maybe a year, if they're tiny now).

#3: You need to read, read, and read some more. There's several good articles out there about the nitrogen cycle, which seems to be what is causing all of your problems (other than severe overcrowding). Also, if you're going to try a fishless cycle (assuming you can get the lfs to take back all of the fish), read up on the particulars of that. I am one of the few who still fishy-cycles, so I don't know much about adding ammonia, etc. Lots of folks on here do, though, so ask away and ye shall be informed...

#4: Don't panic too much, you've done the same thing that all of us have at some point or another. Just make the best of what you have....

Well, at least your ph is fine.... however, ph isn't a hugely significant thing unless it's really out of whack....

While you're reading, do a little research on the types of fish you would like to keep. The danios OR the goldfish are great fish, just maybe not so great in the same tank....

To give you an example, my 10 gallon has a single 3" oranda (a goldfish breed), a 2" chinese algae eater, a 1.5" betta, and a 1" cory cat. That's it. And the goldie will be moving out next spring to it's new home in the pond I'm building. I consider the tank to be heavily stocked at this, if not overstocked outright, since the oranda and the CAE are both very messy fish....

By the way, welcome to AC....(hope I haven't scared you off or anything....)