Tap water good enough?
 

My house is on a municipal water supply. It tastes fine and doesn't appear to be overly chlorinated. It does seem to be on the slightly hard side.

Will the water be adequate for my orchids, or should I be looking at alternative sources?

Thanks in advance for your time and help!!
Cheers, Walt

Generally speaking, water with <200 TDS would be ideal. Most municipalities publish this information. Some plants are more sensitive, others more tolerant.

There are OB members with some expertise in the subject; let them know what orchids you have, their growing conditions and a general geographical area for more help.

---------- Post added at 01:38 PM ---------- Previous post was at 01:27 PM ----------

I just saw that you are in Tampa. OB members from there will also help.

Anon Y Mouse is right.

What city do you live in? Look up your city's water utility web page (unless you are in a small town, there will be one). All municipal water supplies must test their water, and must make the test results available to you.

As Anon Y Mouse mentioned, TDS is important, should be < 200 ppm, less is better. Water utilities buffer (artificially change) the pH of the water to be close to neutral, fine for most orchids, but do check pH. Chloride is not as important as you might think unless you are growing some of the genera more sensitive to water quality (Disa, Phragmipedium, Paphiopedilum), or unless it is really high. Hardness and alkalinity can be important too.

I appreciate the responses. I have experience with marine aquariums and hydroponics, so I have some familiarity with what your saying. I will see if my tester is still working and check at the source.
Many thanks

You need more info than just the tds. As far as plants are concerned water with 200 ppm of predominately mixed calcium and magnesium carbonates/bicarbonates isn't equal to water 200ppm of predominately sodium chloride.

Agree with subrosa. You are better off looking for your water utility's testing report which will provide details on the ions present.

The "testers" for TDS really just estimate TDS from electrical conductivity. Testers provide some basic information if they are high quality instruments that can be calibrated (yours might be OK if you spent a few hundred $ on it). The cheap models costing $50 or less are often not reliable. Better rely on the utility company's report instead.

Mine is calibratable with known samples, but I will look up the utility data. I'm in Hernando county Florida. They provide my water. I really appreciate the responses!!

I have to disagree with some of what I read above.

In nature, the water supplies the plants see is rainfall and dew, which, because they are from evaporation and condensation processes, are nature's version of "distilled" water. As the rains cascade through the forest canopy, they pick up nutrients, but that's on the order of 15-25 ppm dissolved solids, and that's only for the initial part of the rain, rapidly returning to zero as the leaves are washed clean.

It seems logical that plants that evolved in that environment would not view 200 ppm TDS as favorable, let alone ideal. One Clemson paper I read claimed that exceeding 150 ppm of the "hardness minerals" (carbonates of calcium, magnesium and iron) can significantly interfere with the uptake of other nutrients.

I don't know what trreatments your water provider may do, but the USGS considers most of Florida groundwater to be pretty hard.

http://firstrays.com/Pictures/USGS_Hardness_Map.jpg

I agree with you, I was just using the 200 ppm as a point of reference. My tap comes in around 190 ppm according to the meter on the inlet to the ro system that makes the water that goes on my orchids when I don't use rainwater. Except my B. nodosa which can handle some high tds, including a good bit of sodium chloride. That one gets tap water from a fish tank.

I live in an area with insanely hard water, but still use the water from the tap for all of my 70+ plants. They have all been growing very well for a number of years now, with no apparent ill effects.