This is part of a series on Aquaponic Water Testing.

Boron deficiency can be seen as interveinal chlorosis of upper leaves, brittle leaves, and stunted growth. On celery, Boron deficiency is easily noticed as “cat-scratch” marks on the plant stems.

Boron levels in Aquaponics

Hoagland suggests a Boron level of 0.5ppm. Levels above 1ppm can be toxic to plants. Because of this, I greatly recommend testing your Boron levels before you supplement. Supplementing Boron without testing is a recipe for disaster!

Testing for Boron in Aquaponics

Unless you have a LaMotte Smart3 Photometer, the Hanna HI38074 is your only bet for measuring boron levels yourself.

1. Hanna HI38074 (Resolution = 0.2ppm)
   $65/100 = $0.65ea
   I use this test kit, and if you can follow directions, you should be able to complete this titration. Includes a digital pH meter!
   In this titration, one drop < 0.2ppm. That means if your result is 3 drops, your Boron reading is less than 0.6ppm.
   
2. Taylor Technologies K-1541 (Resolution = 0.2ppm)
   $180.50
3. Salifert Boron Test (Resolution = 0.5ppm)
   $29.46/25 = $1.18ea
   For reef aquaria only, expects pH 8-8.6. Don’t use for Aquaponics!
4. LaMotte Smart3 + 4868 (0. 0-0.80, MDL .05)
   $102@GlobalWater /50 = $2.04ea
    +
5. Hach DR900 + 10252 (2 – 50; Resolution = 2.2ppm)
   $289.95@Hach / 100 = $2.90ea
   Gaseous Hydrochloric Acid forms when mixing reagent. Use Caution! Also, this method only has sufficient resolution when used with a spectrophotometer, such as the DR1900.
   +
6. Hach DR1900 + 8015 (0.2 – 14.0)
   $289.95 / 100 = $2.90ea
   Gaseous Hydrochloric Acid forms when mixing reagent. Use Caution!
   + 
7. YSI 9500: Method discontinued

Know of another way of testing for Boron in Aquaponics? Let me know in the comments and I’ll update this post.