by Jorge Cervantes
Reservoirs
Nutrient solution reservoirs should be as big as possible and have a lid to reduce evaporation. Gardens use from 5-25 percent of the nutrient solution every day. A large volume of nutrient solution will minimize nutrient imbalances.
Add water as soon as the solution level drops. The reservoir should contain at least 25 percent more nutrient solution than it takes to fill the beds to compensate for daily use and evaporation.
Check the level of the reservoir daily, and replenish if necessary. Use an indelible marker to make a full line and write the number of gallons or liters contained at that point on the inside of the reservoir tank. Use this volume measure when mixing nutrients.