why has fish died? (little lengthy)

It could be that the red gouramie picked something up from the corpses. He might not have killed them--if they had an internal parasite, he might have become infected when eating them. Nasty, but it happens.

What size tank do you have? How did you confine the red gouramie? What other fish are in there? Water parameters?

Here's another lesson to add to the above - don't use medications, except maybe to treat Ich (white salt-like spots all over fish). Adding medications, especially when you don't know exactly what's wrong, will only stress the fish more and possibly kill them.

An extension of the above - don't listen to fish store staff. Never! Ever! Come to this forum and ask away. And never buy fish from a store that has sick/dead fish. It's hard to find a good fish store, but it's pointless to buy fish that will die.

Now, how big is the tank? Male Gouramis can be agressive; maybe one will be enough for your tank, depending on how big the tank is. Also, have you checked your ammonia and nitrite levels? They can rise every time you add more fish. Don't feed a lot. Trust me, you will NOT starve your fish, even if you try. For now, feed them very sparingly only every other day. They'll be just fine, and you'll be able to keep ammonia and nitrites under control better. Don't worry about nitrates BTW, if you do regular water changes they will never be a problem.

Water changes - do them all the time until your tank settles and is healthy. If anything seems to be going wrong, do a 30-50% water change right away. Water changes will never hurt. The only thing you should add is dechlorinator, I don't care what your LFS says about Cycle and crap like that.

That's all stuff that I wish I knew when I started. For now, don't do anything, leave your tank alone for a few weeks and keep checking ammonia and nitrites. Don't use medications or any additives (including pH adjusters, or magic waste eating fluids, etc etc). In a few weeks, if everything's good, look into buying a few more fish. And research them before you buy! Good luck

More specs on your tank is needed before a good conclusion can be made.

What sized tank do you have? How many and what kind of occupants? What kind of filter? How often do you do a water change? What other maintanence do you do on your tank? We're also going to need to know ammonia, nitrite and nitrate readings.

-Richer

You can punish a fish with solitary confinement floating within the tank, but it can't "learn a lesson." The changed behavior might be a result of ammonia and other toxins in the floating cell-- unless it was in a floating net compartment...

Anyway, these gouramis are males. They don't take well to a rival. There are no gourami "buddies."

Now you have one healthy gourami, which is a good start.

Hanging out here will teach a lot, burt you need a good book too. I always think David Boruchowitz has the best beginner's handbook, The Simple Guide to Freshwater Aquariums.

Originally posted by OrionGirl
It could be that the red gouramie picked something up from the corpses. He might not have killed them--if they had an internal parasite, he might have become infected when eating them. Nasty, but it happens.

Click to expand...

This happened to my dwarf gourami that had picked the corpse of my Albino channel catfish's last meal.