My fish are dying and some are showing sickness symptoms!

Question
Hi Karen, I've been doing research around this site and came to the conclusion that you're probably the best person to answer a few of my questions. I'll start from the top. I recently just set up a 55 gal. fish tank. I've had fish in the past, but the tank was already established by someone else and I'm new to this whole biological cycle and what not. Anyway, my boyfriend is fish crazy and bought a whole bunch of different fish and threw them all in together. There was over 20 fish at one point! And as you can probably guess, a lot of them died. But I've been doing a lot of research on fish tanks, and adding this and that..whatever it takes to make the tank as normal as I could get it. But unfortunately I've come across an array of problems. First, quite a few fish died without any signs they were on their way out! This would include 2 guppies, a swordtail platy, a bala and iridescent shark, a number of neon tetras, and 2 neon danios. They were fine until I woke the next day and they were either missing or pretty much dying. I figure it's because of over population in an unestablished tank..? So I cleaned the tank and all, but now my powder blue gourami has a sore on top of his head right where the top fin starts. Now I was wondering if that could be from my other gourami bullying him or is it a bacterial infection? I looked at the sore closely and it had very very small black dots on it. Next, my guppies have been flashing a little here and there but not as bad as they were when I first added them to the tank. What could cause them to do that? Also, I have a pleco and recently for the past week or so, he's been swimming at the top of the tank and actually turning upside and trying to suck at the surface of the water. I've never seen something like that! I also have a fish (i think its a type of barb, its green and pink with long fins) that neurotically swims back and forth in front of the tank, at all times! He seems fine but I was just wondering if thats a sign of illness or anything? And one last question, I have one of those little aquatic african frogs (I think thats what it is) and I was just wondering, what exactly do they eat?? I hate to bother with all these questions, but I feel I need help from an actual person who knows what they're talking about rather than guessing and diagnosing things myself with random internet suggestions. I would really appreciate if you could spare me some of your time to answer these questions because I'm stumped! I feel helpless and bad for the fish that might be suffering! Thank-you very much, hope to hear from you soon. Oh, P.S. Maybe I could send some pictures or something so that you have a better idea of whats going on with my little fishies! Thanx!

Answer
Hi Kay,
Well, first off, cheers for doing research!!

The main problem I suspect is simply the fact that the tank has just been recently setup and stocked with too many fish. As a result, without tank cycling (no beneficial bacteria) the ammonia levels rise and get out of control and poison almost all the fish or make them very ill. So you are right about tank not being cycled being a problem.

If this might help. Here's an article I've written explaining tank cycling.

"CYCLING made simple~

It is essential to understand the basic principles of cycling your tank. Not knowing how means your whole hobby can fail completely. I'll try to explain it simply-
There are special 'good' bacteria that live in huge colonies in your gravel bed, the filter, and on all decorations and other surfaces. These bacteria convert ammonia into another chemical called Nitrite. Both ammonia and nitrite is EXTREMELY toxic to fish. Finally, more bacteria convert the nitrite into a non-toxic chemical called nitrate which can be allowed to build up with no harmful affects to your fish unless it gets very high. Nitrate is used by plants and is removed by your regular partial water changes.
But these bacteria aren't present right away when you first setup an aquarium, and without these bacteria ammonia will build up to very dangerous levels if you try to stock the tank with a lot of fish the first day or two after being setup. But you need the ammonia food-source to get the bacteria started growing. What cycling means is slowly allowing the beneficial good bacteria to colonize your tank with just a few small hardy 'cycling' fish to provide the ammonia source. When you first add your cycling fish (such as Black widow/skirt tetras, zebra danios, or platies) you'll need to use an aquarium test kit found at your local fishstore to test for ammonia, nitrite and nitrate. Monitoring these levels is essential for keeping your cycling fish safe and for letting you know how far along in the cycling you are.
You'll need to-
* Add 2-3 small cycling fish (Black skirt tetras or Danios)
* Test your ammonia the day after adding the fish
* Feed your fish -very- lightly just once a day
* when your tank cycles, they can have a little more frequent feedings and more variety.
* Whenever your ammonia levels rise above safe bounds, immediately do a 30-50% water change to bring the levels down. This is essential for saving the life of the fish.
* Doing water changes won't disrupt the cycling of your tank. The bacteria live on the surfaces in the tank not free-floating in the water itself. Your aquarium will still cycle properly when even large water changes are done frequently
* Continue testing your water everyday for ammonia and nitrites

*You'll usually notice your ammonia slowly rising at first for several days, then nitrite may rise with a slight drop in ammonia levels... Somewhere along the line you'll get nitrate readings which means your tank is nearing the end of the cycling. Every tank cycles slightly differently. Most aquariums cycle within 3-6 weeks...


*Patience during cycling and tank stocking is essential! Don't forget the importance of water changes and regular testing of your water.

*Remember during cycling that you should not add anymore fish whilst your tank is still cycling. Only have your cycling fish
Once the ammonia and nitrites drop to ZERO and nitrate has accumulated, your tank has cycled!!! You can now begin to gradually build up your stocking level. Add only a few fish every week or so and make sure to test your water the day after adding each new addition of fish to make sure you don't have an ammonia spike, if this does occur a quick 30-50% water change will immediately treat the problem and soon the bacteria should take over and deal with the new bioload."

So Basically all you have to do is work on getting your tank cycled. As for your other questions-

1.) Aquatic Dwarf frogs typically only like to eat bloodworms and other types of frozen food available for your fish at petstores. Pelleted foods or flakes or usually not accepted unless you get lucky.

2.) The little Gourami may just have an injury that should heal eventually with good clean water. Its always possible it may be an infection but just keep a close eye on it and watch for any spreading or change in it.

I hope this helps!!!
Karen~
If you'd like to send pictures, you may send them here-I'd love to see some!

nature_girl2u@hotmail.com