medicating a sick beardie

[hydrosaurus]

Hi
i regularly medicate all of my reptiles on my own.
My trio of beardies seemed to be hit with a bit of a bug.
they had mucusy stool, and were lethargic.
I medicated the male and older female with sulfamethoxidine, iam pretty sure it was the beginning stages of coccidia.

now
after the adults have cleared up, the smallest female is showing signs of illness... ive been medicating her with a 1/4 of a pill. i belive they're 25 mg's. same dosage i gave my other beardies.
and it isnt working at all.

I have flagyl, and panacur as well.... but neither do anything for coccidia.
any help would be appriciated