Randomly I ran across an ad for $15 rain barrels on Craig's list and ordered a few. After some research realized that side by side wasn't a good model and ran across a guy who had stacked them in a tower vertically. Planned it out (I know the plan image shows feet, its inches not feet) and started building the tower. Barrels are 55 gallon drums with 2 bungs both 2in. One is standard NPS the other is something called Buttress. Found the fittings on line for the buttress at flexpvc.com and ordered them. Decided to include the anemometer on top for the height while I was at it, and found that I didn't have to cut the top barrel as show in the plans.
Several months after install I noticed one corner sinking. This is probably due to there being banana roots under it decomposing. Jacked it up with the car jack till level, dug it out some and filled the area around the post with concrete. That seems to have solved the issue.
The pressure coming out is almost useless. Its enough for the soaker hose going to the bananas right next to the tower but not much else. Part of the problem is the tower is downhill from anywhere I would want to use the water. It takes 2.3ft of height to produce 1PSI.
Drip irrigation needs 10-25 PSI, real sprinklers need even more. Household things like the toilet pump need 20PSI. Garden hose nozzles 35PSI.
Since it physically cant go any higher getting more pressure is a problem. I would like to use this for a recycling fountain/pond for the bees. The general idea is an open reservoir that only fills to a certain level, and is pumped back up to the top of the system so it constantly stays fresh.