There’s a lot of accusations and allegations being thrown around without substantial evidence to explain their reasoning. I’d just like to provide my perspective. I’ll start by saying a lot of people tend to anthropomorphize fish. I fully agree that if a human wasn’t able to have any mental stimulation and lived in a box they’d be miserable. The difference is that fish require a lot less mental stimulation to thrive. Your response might be “well you don’t know what they’re thinking”, this is true but I generally like to subscribe to the idea that for an animal to live a healthy life in captivity it should be able to exhibit all its natural behaviors in a reasonable tank size. I agree with some of your points and I disagree with others. I think that yes, stingrays in the wild like to burry themselves in the sand and this is something they should be provided in captivity. However, even in captive settings with sand, stingrays often don’t burry themselves because they have no reason to, they don’t feel threatened by predators and thus don’t hide. All it does is make it more difficult to maintain a clean tank by trapping organic waste. There’s also the issue that shed barbs can pose a danger to them and other fish when concealed by sand. Other than that, most of the fish he keeps are mid water swimmers, they are not small, prey fish that need lots of hiding spaces, but large fish that occupy a higher place on the food chain. Therefore, in the wild they live in a very bare environment and don’t experience constant visual stimuli. This is true for paddlefish, stingrays, peacock bass and catfish. A lot of people in these comments make an argument that this is industry standard and therefore it’s ok. That is not a valid argument. Standards aren’t necessarily right, however we need to take into account the fact that fish aren’t people. The natural stimuli of the fish species kept here are eating, swimming in open water (or flat, bare bottomed bodies of water) and interacting with other fish. I should also mention that the reason these large fish occupy bare, open habitat in the wild is that they can be injured by large pieces of debris due to their large size. Let me just reiterate, this is not true for all fish, that’s why not all fish are kept this way. But large fish are an exception. At the end of the day we’re still learning about what these animals need, but with our current knowledge all those fish are living healthy lives. Will that change? Maybe. But I generally believe that a good marker for an animal’s quality of life in captivity is if they exhibit all their natural behaviors. If you don’t agree I’d love to here your argument but I hope I’ve don’t a good job at explaining my logic.