thank you for the replies. i've decided to wait till cupramine treatment is finished. only after that i'll start the api general cure treatment.
as for copper not eradicating flukes, you guys might be right but seachem's claiming that cupramine does eradicate flukes. this is from seachem faq:
"Q: Can you tell me if Cupramine™ is effective against gill fluke?
A: Yes, Cupramine™ effectively eradicates ectoparasite of both freshwater and marine fish. Please be sure to follow all directions on the product, make sure that you do not mix with any other medications and turn off your UV sterilizer. Please let me know if you have any further questions."
anyway, i think most people use prazipro for a reason and that reason is that praziquantel eradicates all kinds of flukes. so i'll do what most people do and use general cure which contains praziquantel as i could not get the prazipro.