Wow...some of these photos are amazing!
I don't have any pictures, but I do tend to hoard them...
I started with 3 ten gallons...then I upgraded to 20 gallons...and now I've got my first 30 gallon...but I keep all the old tanks, even though there's nothing in them. I tend to feel bad for any of the fish in the smaller tanks, so eventually everyone gets an "upgrade" into a larger one. But...just in case...I keep the old ones as well. :)
So far, the list includes:
3 20 gallons
1 30 gallon
3 10 gallons
2 3-5 gallon plastic bins for temp homes/hospitals
3 bowls, again, for temp homes and for learning to swim in larger and larger spaces once they come home from the Cups Of Death. I take them up a bit at a time from a 1 gallon bowl to a 10 gallons of water (either a single tank or a larger one divided). Everyone eventually lives in at least 10 gallons.)
All of mine are in my bathroom. I know, that sounds terrible...but I've got one of those "jack and jill" divided bathrooms, so there's a hallway with the two sinks and the linen closet, then a smaller, separate room with the toilet and shower/tub in it. I've got 1 20 gallon, and 1 30 gallon in there, and 2 more 20 gallons in the hallway portion, one against the wall on a stand, and the other on the counter between the sinks.
I ended up putting them there because so much easier to clean (water and drainage is literally RIGHT THERE), and moreso because my house is old...and the windows are drafty, and the bathroom is one of the warmest rooms in the house, so temps can stay pretty steady. (Even with tank heaters, some of my rooms can vary by up to 7 degrees between day and night depending on the weather, and I've yet to find a heater than can keep up.) And I get to visit my boys every day when I get ready for work, and then again at night when I come to take a shower. :)