Good point about their natural water temps, that's likely true -- though soon after they're caught as tiny little babies and brought to fish shops/farms they're put into tanks with quite a bit warmer water temps. Also I'm not saying these higher temps are ideal for overall long-term health (in fact the opposite is likely true), just that they probably stimulate feeding.
In fact I'd love to cool down the water in all my tanks, but short of buying chillers, which are very expensive here, esp. larger models, this just isn't practical. The rainy season is on it's way next month, so looking forward to some slightly lower temps.
With your Dats and even more so with peeps in USA/Europe, the fish also had to go through more arduous international trips to get to your fish tank, whereas mine is more direct, much less stress on the fish, so not surprising survival rate is lower outside of Thailand/Vietnam unfortunately.
And thanks for the compliment, though imho awesome will be if I can successfully grow him to 10-12"+. I've read about the Sudden Death Syndrome thingy with Dats, esp. NTT, that has me a little worried in the back of my mind, but nothing I can do about that but try my best -- starting with current diet, he really is getting fat, which isn't healthy.