For those just getting started, my experiences and decisions are chronicled in the link below.

1-Utah-Aquaponics-System-Part-1-(Feb-2009)

Click the Links at the bottom of each blog entry to follow my journey step by step.
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A mature Aquaponic system generally only needs minor additions of Iron and perhaps Potassium, Magnesium or Calcium. However, variations in the PH of the source water, the quality of the fish feed, PH adjustment method, and media used in your grow beds can all affect the nutrient balance. There are several ways of knowing various levels of the key components of your system. The most complete and accurate is to send a sample of your system water to reputable water quality lab for testing on a regular basis. However, there are many individual testing kits for various elements as well as several complete kits. In this article, I review the usefulness of several such kits. ...

One challenge of raising flowering-fruiting crops in an enclosed environment is that there are no natural pollinators to assist in pollinating the crops. Without adequate pollination our crop production can be substantially diminished. ...