Honey Gourami possibly Insane?

Gourami

While out stocking my tank, a small Honey Gourami caught my eye. She was floatin at the top beneath a filter. She was cute and obviously sickly, but my dad just had to get her. She was doing fine in my tank, thriving in fact. But when I woke up this morning she had a big stress stripe and was on her side. I immediately isolated her. She appears to have "dirt" on her tail, and hasn't eaten since I brought her home 2 days ago. I let her out, as she seemed to be getting better. She went on her side again, as honeys get stressed easily. She began swimming in no time. Bit now she almost seems to be squirming every once and a while, an when my danios get to close, she chases them. I have no idea what's wrong with her! Also this morning one of my danios tail was White and shredded and gone! I euthanised him as there was no hope, but could that have something to do with it? Ph 6.8, temp 76, and I have hard water. Danios, corys, and one Honey Gourami. Help!

Fredsterbit

Might want to specify how hard is the water. Also try and find out what the ammonia, nitrate, and nitrite levels are. Now... you described there was some "dirt" on the Honey Gourami's tail. Could you describe that a bit more? More description on how big the tank is and what is in it might be helpful too.

redchigh

Honey Gourami are normally calm, but I've seem them get a little territorial. Danios should never be placed with gourami- the danios are way too active.

We need to know your water paraters, but it *could* be Dwarf Gourami disease...
Dwarf Gourami disease is fatal, contagious, and has no cure. (And only affects Dwarf Gourami)

Symptoms are:
Lethargy
Dark splotches, especially on the belly
wasting away