I have rainbow fish who have a white pimple like thing around their eyes and mouth, eventually causing death. I've been getting info from fish stores. 1st I was told to use Artemis, it didn't work. Then I was told to use Melafix with Pimafix.

Hey Linda! It's tough to say without seeing a clear picture of the fish - as well as knowing your tank's water parameters. The two medications you mention most definitely do not treat the same ailments. Please shoot an email to our team and they'll assist you further, and good luck with your fish!

I'd avoid taking advice from pet stores, they are just regular retail workers. Find a Facebook group like Aquarium Keepers. Melafix and primafix are remedies and won't fix anything. Test ammonia, nitrite,and nitrate.... It's highly possible it's a viral disease lymphocystis.