How to Convert Oil Tanks to Water Tanks
- 1). Drain all the excess oil out of the tank by opening the drain valve and allowing the oil to run into a bucket.
- 2). Spray the inside of the tank with water using a high-pressure hose. Keep spraying the tank until the water coming out of the drain valve runs clear.
- 3). Close the drain valve and fill the tank halfway with water. Add 2 cups of trisodium phosphate.
- 4). Place an air hose into the water and turn it on. This will keep the trisodium phosphate mixing into the water. It's best to leave it running for at least eight hours or overnight.
- 5). Drain the water solution out into the garden, then hose out the tank once again.
- 6). Replace the oil pipe valve at the bottom of the tank with a wider water pipe. Unscrew the original pipe attachment. Take it to your local hardware store. Buy a larger water pipe with a tap connector and also purchase a galvanized bell reducer. This allows you to connect smaller pipes to larger pipes.
- 7). Screw on the galvanized bell reducer and water pipe with a pipe wrench. Put water in the tank to test the connection. If there are any leaks, cover them with PVC cement.
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