Water Types Good for AeroGardening

If your plants are turning yellow and not growing, it may be due to the type of water being used. The water used in aeroponic gardening needs to fall within a certain range of pH and dissolved-mineral content. Most city tap water is treated so that it falls within this range, and works fine in the AeroGarden.

However, if you are using "hard" water, which includes some tapwaters (especially in Florida and the southwest), well water, spring water, or "softened" water, you will experience germination and growth problems in your AeroGarden. The dissolved minerals in the water will block the proper uptake of the nutrients by the plants, which will inhibit germination of seeds, severely stunt growth, and cause  yellowing of the leaves. Hard water is the number one cause of growth problems in the AeroGarden. Most water filters do not remove minerals, as explained in more detail below.

If your plants have yellowing leaves or stunted growth, we recommend switching to bottled distilled water (not  "spring", "drinking" or "purified" water) instead, which is available at most supermarkets.

If you are on a well in the country you might also consider just refilling a gallon jug from a city tap when you go into town. 

About Filters
Most home water filters do not remove dissolved minerals. They are designed to remove contaminants such as organic solvents and chlorine taste, but dissolved minerals are tiny ions which are far too small to be filtered out. The only filters that remove minerals are industial-grade reverse-osmosis filters, such as the commercial “de-ionizing” filters used by certain manufacturing industries.

Water Softeners
Water softeners work by displacing dissolved minerals with sodium, which prevents mineral deposits from forming in pipes and on bathroom fixtures. The sodium in softened water will also cause serious problems in the AeroGarden, by blocking nutrient uptake by the plants. If you live in an apartment, be aware that many apartment complexes put water softeners on the water to the entire building to prevent mineral build-up in pipes.

Once water has been through a softener, it will not work in the AeroGarden, even if later run through a reverse-osmosis filter. Only industrial-grade reverse osmosis filters ("de-ionizing filters") are actually capable of removing sodium ions. If you are on a well, however, where calcium and magnesium are high but sodium is not, a reverse-osmosis filter may work for the water in your AeroGarden (provided the pH of the water is normal).

Other Types of Water Treatment
Distillers do remove minerals, by heating, vaporizing and re-condensing water, leaving the mineral deposits behind. Pure distilled water works very well in the AeroGarden, provided it is within normal pH range.

Some people have also tried to use the water collected by their home dehumidifiers, believing it to be distilled, but in our experience, this water does not work well in the AeroGarden.

Collected rainwater is also usually problematic, as it can contain minerals that it picks up along the way, as well as sometimes being too high or too low in pH.

Chart of Water Types