It's about money and skill.
Space is at a premium in a store, and enough space for proper quarantine takes a lot of rent money.
Next comes knowledge.
I'm gonna tell you something guaranteed to make a lot of people mad.
Most fish store owners have no business being in the fish business.
That's right, I said it.
These clods can't tell one disease from another, can't tell you the correct way to cure one once identified, and frankly don't even care.
In a more perfect world, the pet industry would be regulated in the same way the SCUBA industry is regulated, with both shops and hobbyists having to pass tests and be certified. We'd see some tremendous improvement in short order.
Anyway, sometimes you might find a shop owned by someone who really knows what's what, but if you do it's still likely that his shop doesn't spend much effort on quarantine for one simple reason. His competition doesn't.
Clean fish cost more than dirty ones.
Customers demand lower prices.
Mixing clean fish with dirty ones makes all the effort and expense a total waste.
My old shop was a big one. 6600 gallons. A full third of the store was just quarantine. That's 2200 gallons worth of tank space full of fish that were not for sale. It was a BIG expense. I did it, though, for the reputation it would give me. I should point out that I'm a bit of an ichthyopathologist who knows the full ins and outs of proper quarantine. ( I was also the Senior Aquarist at a public aquarium where quarantine HAD to be perfect and fully effective )
To put it plainly, I offered my customers the very best fish that money could buy, and the word spread quickly. I had customers coming from over 150 miles in every direction.
However, I didn't have enough of them.
My local customers didn't appreciate everything I did for them. A few did, sure, but most of them continued to shop at competing stores with lower prices. Naturally, the fish I sold them got infected by the dirty fish they bought elsewhere, and everything was for naught.
If the internet was a big thing back then, I suppose I could have made it as a mail-order place. Foster-Smith / Liveaquaria dotcom wasn't around yet.
Anyway, I learned the hard way that customers cherish low price above all else. They SAY they don't, but when given the choice, they'll pick the cheap dirty fish that "look okay" over even guaranteed to be clean ones which cost a dollar more.
