Measuring minerals in the reservoir. What is a TDS/EC Meter?

TDS, the total amount of mobile charged ions, including minerals, salts or metals dissolved in a given volume of water, expressed in units of mg per unit volume of water (mg/L), also referred to as parts per million (ppm).  A TDS Meter is a small handheld device that measures this. Total dissolved solids readings help to indicate the density of solution which can help to determine when it’s time to add nutrients. Temperature can affect TDS/EC meter readings.

Do I need a TDS Meter to grow successfully with my Tower Garden?

ABSOLUTEY NOT! Thousands of families all over the US have been growing Tower Gardens for the past 4 years or so without using TDS Meters.  If you follow the instructions (a summary of when and how much Tower Tonic should be added can be found here) you really do not need one.  However, some prefer to know exactly how much they need to be adding and a TDS meter gives you that information!
What should the readings be in a Tower Garden?
Generally, readings should be approximately 1500-1800 ppm .  In the summer months reduce this to approximately 1000-1500 ppm. “Why lower in the summer?” you may ask.  Because the water evaporates and the minerals do not.  Having too much tonic can be just as bad as not enough, especially in the heat! Learn more here…

How much does a TDS Meter Cost?
TDS Meters range in price from $15 up to a few hundred dollars for top of the line commercial units!  The one I own and use for our Towers at home cost approximately $22 and can be found here on Amazon. This one measures the ppm and the temperature.

How do I use it?
All meters are slightly different but do the same thing.  They will need to be calibrated here.  As you are testing for water around the 1000ppm range you will want to purchase calibrating fluid that is 1000ppm.  Check the guide for your meter for more information on the specific fluid to purchase.
Over time and you will need to purchase calibrating fluids.  They are usually less than $10

NOTE: Be sure to check your pH AFTER adding minerals.  The minerals are acidic and will lower the pH.

Still don’t own a Tower Garden yet?
You can purchase one here.