Fertigation tanks from totes

A tote as a stock tank

In a typical set-up, a tote holds a concentrated or diluted fertilizer solution. An injector or a pump draws from it into the irrigation line. The tote sits on a level pad close to the pump, with a screened cap and a bottom valve for suction. Stock tanks should be opaque or shaded, since light feeds algae in a nutrient-rich solution, and algae clogs emitters.

1. Choose a tote that held a compatible or harmless product.
2. Rinse it until the water runs clear.
3. Place it on a level pad near the injector.
4. Fit a screen and a labeled valve.
5. Fill with water first, then add fertilizer slowly with the pump running.
6. Label the tote with the product and the date.

Compatibility

Some fertilizers react with each other, forming solids that block lines. Calcium and phosphate are the classic pair. Keep a tote for each stock solution if you run incompatible products, and do not switch a tote from one to the other without a thorough rinse.

Containment

A leak of concentrated fertilizer is a pollutant. Place the tote in a spill tray or a bermed pad that holds at least the tote's volume, and keep it away from drains, ditches and wells. In South Florida, where the water table is shallow and canals are close, containment is not a nicety.

Records

Write down what each tote held, the dates of fills and the rinse record. If an inspector or a customer asks, a notebook answers in a minute.

Calibrating the dose

Know your injection rate and your flow before you mix. If the injector draws one gallon of stock for every hundred gallons of irrigation water, a 275 gallon tote of stock lasts for 27,500 gallons of irrigation. Check the ratio with a measuring cup and a bucket at the start of every season, since injectors drift. Record the date and the reading in the same notebook as your rinse log.