This tank came with a 2 inch bulkhead fitting already installed. It’s for connecting more tanks together and for draining the tank quickly. Or, we can use it for drawing off water.
I’ll be adding a float and screen to this tank so I can draw off the cleanest water that’s just below the surface and away from any sediment in the bottom.
Jump to:
Off-Grid Rain Tank Part 1 – Pour the Tank Foundation
Off-Grid Rain Tank Part 2 – Build the Tank Surround
Off-Grid Rain Tank Part 3 – Tank Plumbing and Fittings
Off-Grid Rain Tank Part 4 – Install a Solar Powered Pump
See the Youtube Video Part 1 or Part 2 or Part 3 or Part 4
Off Grid Rainwater Harvesting System – PART 3: plumbing and tank fittings
(this is a transcript from the video)
I’ll add a ball valve to this existing bulkhead fitting. I first add a reducer down to one and a half inches. I didn’t have channel lock pliers big enough for these so I used the biggest wrench I had. Then I’ll add this short nipple, and then the ball valve.
Before I can add the float and screen I need to assemble the parts first. I BOUGHT some of the tank parts and decided to MAKE some of them from existing fittings.
Float Hose Assembly
I cut the float hose down to a length I though appropriate for the height of this tank. About 2 feet taller than the tank I thought would be good. There’s a barbed fitting that goes into the inside part of the bulkhead fitting first. Then the clear flexible hose goes onto that. It was a tight fit and tough to get this on, even with some soapy water as a lubricant. And a stainless steel hose clamps secures it.
Then the screen and float goes on the other end. And a lanyard is tied to the float. This will keep the screen up off the bottom of the tank when the water level gets low.
I’ll need to drill a hole in the tank for a bulkhead fitting for the hose that’s connected to this float. It will be around the back at the southeast corner. I’ll use a hole saw for this and drill this hole 4 about inches off the bottom.
Drill into Tank with Hole Saw
Getting the bulkhead fitting through this hole can be tricky. I first screwed in a barbed fitting into the bulkhead fitting. Then I tied a string to the barbed end. And taped it too.
The other end of this string is taped to the end of a pipe.
Then this pipe is set in the tank with the string end resting on the hole I drilled. I then carefully remove the tape and pull the string through the hole.
Feed String through Hole
I remove the pipe from the tank and lay in the hose and float assembly. Being sure that the end of the lanyard on the float is still outside.
I now pull the string to bring the bulkhead fitting through the hole and attach the nut. I snug this up with a wrench.
I’ll be connecting this fitting to the mini pump house later. But for now I’ll add a ball valve so I can make the tank water tight. I detailed the construction of the pump house box in Part 2.
To find the best spot for the tank inlet I sighted down a large speed square. I lined up one edge to the curb and marked the point where the 45 degree edge contacted the tank.