Grozine Cultivation Tech & Lifestyles Mag Issue 12 | Page 51

Besides cost, there are also some practical considerations when you are working with thousands of gallons in a hydroponic reservoir versus 100L Reservoirs like you might be at home in a spare room: -time it takes to drain and fill a reservoir -the number of plants at any given moment that are depending on a stable and consistent solution -the cost of water -availability of water for commercial crop production -water quality, and treatment (scale of and equipment) -the cost, time and potential for error in mixing a fresh batch of hydroponics fertilizer solution In short, the goal is to keep a long working life per hydroponics reservoir mixed from “empty”. Through experience and research, American Hydroponics has some great growing tips to share on the subject of managing and maintain hydroponics reservoirs for optimal crop growth while keeping in budget. Examine the water quality. Water tests are easy, affordable and typically accurate. There can be fundamental differences in how a fertilizer formula will perform in one source water over another* Source fertilizers that are stable, ie “clean” synthetic fertilizers. An abundance of organic materials may cause instability in things like pH, affecting nutrient ability and creating stresses that can lead to crop troubles. Select a fertilizer blend that is intended for your plant type and season-look for formulas that provide good results consistently and that come with information on what type of water quality is recommended, ie upper and lower limits. Determine how the level of pH adjuster (ie Phosphoric Acid or Potassium Hydroxide) will contribute to the elemental value of the fertilizer solution over time-because it will. Keep the reservoir topped up with fresh water. The reservoir may be purged by as much as 50% and remixed-often up to 3 or 4 times to extend the life of the nutrient solution while not compromising cropping performance. Using accurate monitoring equipment for EC, temperature and pH in the nutrient solution, and by developing a basic understanding of how plants use fertilizers, growers are able to run for several months in instances without completely draining and changing the hydroponics reservoir. When you understand plant fertility, and more recently, have access to ion-specific nutrient monitoring equipment, you can add individual fertilizer components as needed to “bump” individual mineral values (for example, Calcium) to replace what has been taken up by the crop more rapidly over others due to seasonal conditions or the working life and maintenance of the fertilizer solution. All this adds up to better “fuel economy” and less issues associated with redirecting spent nutrient solutions and mixing fresh batches to the tune of thousands of litres of water and a respectable dollar value in good quality fertilizers. Above: Commercial growers resources via American Hydroponics VOLUME 2 | ISSUE 12 51