Here is what I made about 2weeks ago. Each can is 32 gal so I have I have just under 64 gal of rainwater when full. The location of the overflow drain does reduce the total capacity, but not by much. When the cans are about 1/2 full there is enough water pressure to fill a 5gal bucket in about 10 sec. The only problem is the left can has slow leak at the drain, I may just have to cut it off and reapply silicone to seal it up. Anybody got any ideas on keep the water from smelling like swamp water? With the first rain after I got it up, there was a LOT of pollen in the water, well that pollen floated to the top and is now "pond scum". Primary use of the water is to water the garden, hopefully I'll keep my water bill a little lower this year and I wont be putting chlorine, flouride, etc. on my plants (all crap that is in my city water). Edited to add: the end of the spigot is threaded so I can attach a garden hose to it as well. re-edited to fix image, no my image, but it's what I made.