Please help - tank disaster!

That's great that everything is starting to do better. I would wait a few weeks before adding anything. When you do start to add fish do it slowly. I think part of the problem that you had besides that the tank wasn't cycled is that you added to many fish at one time. Start by adding only a couple fish at a time and wait a few days to add more. We are impatient by nature and it's really hard to say no to a child looking up at you with those sad eyes to get more fish. When you add fish slowly it lets your system get used to the added bio-load. I would set up the desk top tank as a quarantine tank in the future. Just my .02. Good Luck.

As far as the filter read the directions on the medicine they usually will tell you when you can put the filter back in. Some you don't even have to take it out .
 
Well I have good news! After doing water changes and putting the carbon back in, nitrites and ammonia have been at 0 for 3 days. All the fish are super happy and doing well.

So...yesterday I bought a dwarf gourami. I am SO happy - I LOVE gouramis. They have so much personality and this one already likes me. When I go to the tank he swims up to me and has this little wiggle he does. He's a dwarf (ofc) and is truly a beautiful fish - the red flame kind with the electric blue on his top fin.

The tank actually looks really good with just the four fish - there are so many plants and crystals in there that I don't know if we will add any more or not. I'm going to try to take some pics to post - thank you again for all of your help!
 
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