In a quick search, I found some online pharmacies that sell fish antibiotics. Back when I was first trying to get some, it was always a little flaky. Seems to still be the same with some not selling them, requiring prescriptions, the places that sell them seem to come and go.
I remember the last time there was a rumor that they had halted the sale of antibiotics. I’m sure they want to. But that would completely destroy the home fish hobby. Who’s going to take their fish to a vet? Plus they seem to need antibiotics quite often. I imagine the place is selling them are looked into and that might be why they change whether they sell them or not, or new ones pop up only to disappear shortly after.
Here’s what I found today using duckduckgo, this was just the first page so there’s more. About half the ones that showed up no longer sold them or the domain was even for sale.
Amoxicillin 500 comparison 100
https://thefishantibiotics.com/collections/fish-antibiotics
$39.99
https://fishmoxfishflex.com/collections/amoxicillin-fish-antibiotics
out of stock
https://aquaantibiotics.com/aqua-antibiotics/aqua-mox
$36.95
https://aquaantibiotics.com/fishbiotic-amoxicillin-500mg-60-capsules
$39.95
Cal Vet Supply
$26.99
This was just an interesting article:
Online availability of fish antibiotics and documented intent for self ...https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7470343/
Thanks for that info. I have used FishMoxFisFlex and have been getting emails from them about being unable to sell product because of FDA issues. So maybe it is just them