Today at petsmart this lady with her 2 young kids and husband asked me if she could put a female and male betta together, I told her no and she complained how the other worker said she could. I explained how the male will kill the female or vise versa if they don't want to breed. She then asked what fish she could put with them and walked over to the tiger barbs where she tapped her fake nails on the tank wall scaring the fish. I told her they are tiger barbs and will nip the bettas fins then showed her all the betta compatible fish and those that aren't compatible.
Now I ask the important question, how big is the tank. Her young daughter walks up with a 1.77 mini tank that she plans to put the male and female together in because she's determined to get them even though I told her they aren't going to do well. I quickly tell her the tank is only good for a single fish. After telling her this she buys a male guppy(a fish I told her not to get because of the betta) and a otocinclus. She wanted some platy's as well but I told her the tank was way over the bio-load and that her fish weren't going to do well.
On a good note I helped these two girls a lot with their bettas. I explained the dangers of plastic plants, and water change schedules and the importance of having at least a 2.5g. I also referred them to this forum so I hope they check it out.