Just throwing it out there, I have 3 basic questions I try to ask every single customer every day. How long has the tank been set up? What size tank? What is the current stock? I do my best with every customer to make sure they aren't leaving with something they can't handle, they know what they're buying inside and out, and they don't run into any surprises down the line. Working at a LFS I can say that there is a surprising amount of people who come in and seriously will not listen to reason. I actually had a customer come in and ask how big a silver arowana and RTC would get if he put them into a 10g tank.. This is no joke. I tell him that can't happen, they will outgrow it fast and they'll be unhealthy in the process because of the major lack of space. He shrugged it off and basically tried to get me to tell him it would work and it got to a point where I ended up passing him on to a coworker because I couldn't bring myself to catch these fish, who I'm sure met a sad and undeserved demise in this guy's tiny tank. I guess the point is it can be two sided sometimes, there's going to be poor care for fish from time to time but as was stated before it is a business and more often than not a shop has been around long enough to know what they can turn around between orders so the fish more often than not won't be in such crowded conditions for long. I personally can't go home at night knowing I went for a quick dollar instead of properly informing someone about the needs of a fish and making sure the well being of the fish and customer was met and I encourage all of my coworkers to do the same. It's not so much the business side of it but more that I love fish too much to not step in and make sure they aren't mistreated be it something as small as some tetras or as large as my personal favorite a datnoid. My take, the key to success in a LFS is honesty to bring customers back and knowing what you need to turn around between orders and being able to do it. Obviously there's a lot more that goes into it but these are the main things I try to bring to the table every day as an employee.