can you fit a heater and a filter in it...homemade sponge filters can be quite small and accomidating. id be happy to help you make one if you need assistance so just ask...does he have room to actually SWIM around (not just turn around)...and could you put some plants or decor in there to keep him entertained?
if you can say yes to these questions, than its fine. its just with smaller volumes of water it is harder to maintain the chemistry, but that's why you test your water and do water changes.
good luck with him...he's purdy
regards
Your picture only shows the corner of whatever he's in so there is no way to tell you unless you can give how many gallons it is . There's an aquarium calculator on here, put the dimensions in ( I find inches easiest ) and it will tell you haow many gallons the tank is.
No. It is not a good home for anything let alone a fish. You can check garage/car boot sales or craigslist/newspaper cassifieds for a much bigger, cheap ( sometimes free ) tank.
Some of them even come with equipment and decor, and if not, a sponge filter and 25-50 watt heater can be bought on ebay for not too much money.
It's just a 1 gal tank?
I agree that that is much MUCH too small to be used for anything other than a temporary tank. And even then... only for a few days.