My mum buried a bath tub in the front yard years ago, we had some gold fish in there, then the front yard got overgrown, my parents moved overseas and the bath/pond was forgotten about. Last year I was clearing the front yard and discovered the pond and there was still a huge healthy bright orange gold fish happily living in there! Its still there today and the only attention that pond/bath gets is when I part the knee high grass occasionally to see if its still alive! It has some wart like growths on its head (probably from years of exposure to our Aussie sun!) but other than that its fat and healthy! LOL!