would you have said anything about the overstocked tanks in this situation?

No. The Asian/Pacific Rim concept of aquaria is completely different than the Western World. I have personally had excellent dog or cat dinners over there that wouldn't be accepted here at all. No need to assert your viewpoint on them. I have seen extremely overstocked tanks by our standards and the fish perfectly okay.
how does cat taste
 
I would have said something if the fish looked to be unhealthy or otherwise suffering because of it. My mom had a white cloud she kept in a tiny pint jar (those ones they say are for bettas), which would be terrible by most people's standards. But it also had hornwort, and got fresh spring water twice a week. It lived to be about 12 years old, quite happy and perky.
 
I wouldn't have mentioned the overstock in either tank. I.would have asked about the fish tho, lifespan and health. Depending on how the conversation went I may have mentioned that its considered too many fish where I'm from and try to have a discussion on the pros and cons of having so many together in the smaller tanks. That's all depending on how open minded the cousin was/is. If They get defensive then I would've dropped it. LOL
 
No. The Asian/Pacific Rim concept of aquaria is completely different than the Western World. I have personally had excellent dog or cat dinners over there that wouldn't be accepted here at all. No need to assert your viewpoint on them. I have seen extremely overstocked tanks by our standards and the fish perfectly okay.
I totally agree. Scary isn't it! For the past year and a half I've maintained a 26 FBH with 6 6" Parrotfish and a 5" Tinfoil Barb. The owner has had his current group of fish in this tank for almost 10 years. The system is set up to deal with the potential chemical issues and the fish were raised together the whole time. Would I keep such a tank myself? No way. Would I tell someone that it's wrong for them to do so in spite of years of evidence to the contrary? No way. I mentioned it to him when I first took over the tank that they would appreciate a larger tank and that was it. And this is a guy I see once a month, not a family member.
 
I wouldn't have said anything unless I was asked, but I might have left them a notecard with some good research websites and forums, but I don't think I'd have said much.
 
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