chines medication

I have got an internal bacterial infection in one of my adult discus which required Kanamycine sulfate ,unfortunately a lot of fish antibiotics which are american manufactured is not allowed to come to Australia (ebay or Amazon etc ) so i had to search else where and i have found two chines manufactured and supplier on e bay who have almost every thing and very reasonably priced as well so my question is has any body have used chines aquatic antibiotics and what is the experience , my concern is mostly the fact that i have no way of knowing if for example the true concentration of the active ingredient is right or not .
I have ordered some oxytetracycline anyway but i thought i ask if any one has any experience good or bad .

I bought them, but haven't used them yet. Took about 2 months for delivery from China seller on eBay.

I use local veterinary stations for buying this kind of medications . They are readily used for dogs and cats , and vets usaualy have them at hand .
They should come with information sheet about their active ingredients in percents or per Milliliter .