for me, it tends to be 1000 gallon tanks are less fun. going over 500 really makes it kind of boring if your tank is so wide you can't see the fish if they are on the far side of the tank as well.
i had a 1000 gal at the shop i set up but it backfired when all the fish would hang out in the far end of the tank and it was a good 5 feet to the wall. you'd have to make it long and high to be worth the size as i find it hard to enjoy fish in a 1000 gal any more than in a reef. the point of a tank is to force the fish to be seen any time you want to see it. otherwise, build a pond and imagine how happy your fish are rather than watching them.
