Same fish, same problems

[Nameless]

This is the same fish I keep having problems with. She is a betta female, and now lives in a 5.5 gallon next to my other fish tank.

She has had pop eye for many months now. Her gills stick out a little, making her head look disproportionately big compared to her body. Sometimes her scales look like they are sticking out a little, and once she even looked like she had completely pine coning dropsy. Her body is also a little deformed looking sometimes, like she is bending awkwardly. Her blue color is faded and she has ich.

In fact, this is her second round of ich. A while back I treated her for ich for 15 or so days, and it was all gone. But two weeks later I noticed that the ich had returned. I read online that ich was a parasite that had to be introduced by a sick fish, and once destroyed it would not return until another fish with ich was added. Well, Noel didn't have ich when we got her, nor did she get it when her tank mate was a snail. Nor did she get it when her tank mate was two algae fish. She also had live plants added (which all died off during an algae infestation), which introduced pond snails. She didn't get ich from them either. And after 15 days of treatment the ich still returned.

So I am starting to believe the other theory that it is something that is always present in a tank, but only attacks weak fish. But I don't know what is wrong with her that would cause any of this.

Her tank has zero of everything, Amm, trite and trate.

I put Prazipro in there today as a possible cure before I noticed the ich had returned. Hopefully the prazipro will help real problem even if it won't cure the ich.

Anyway, I have no idea what is wrong or what to do! Please help =(

[lohachata]

is the tank filtered and heated to 80+ degrees ?
do a water change..make sure of filtration and heat...treat with melafix..make sure tank is aerated...

[Nameless]

The tank is filtered and heated (always has been) and I do a 50 % water chage every week. In fact, I did a water change yesterday before adding the Prazipro. I've had her on melafix before, for two weeks in a row. But I'll add more today, if you think it will help. =)