Tap water parameters

[bogdan]

Hello
I recently got a water quality report from the local company and am worried about some of its parameters:

Electrical conductivity 594 µS/cm (quite high, I guess)
Total hardness 17,9 °dH
Na+ 17,4 mg/l
Cl- 25,5 mg/l
And quite a lot of nitrate, but that's orchids' paradise.

These seem fine
pH 7,39
Ca 91 mg/l
Mg 23,1 mg/l
No added chlorine for disinfection.

Basically it's hard water. Taking in account the sodium and chloride, would this water work OK using it at half of the waterings? The plants are Cattleyas and Paphiopedilums. For example, this week I am watering with distilled/RO water and Rain-Mix (that has Ca and Mg), next week tap water with nothing added, usually they go in for a long shower, and so on.

Thank you

[estación seca]

Your sodium and chloride content are low enough to be acceptable for most orchids. The calcium content is also not that high. Hardness is measured in different units here, and my water report doesn't have a conductivity measurement. But most hardness is due to calcium and magnesium; your water is tolerably low in both.

I would think your water would be OK to use on most orchids as it is. If I were you I would reserve the RO for the very sensitive plants, and perhaps a once-monthly good flush. But I would use your tap water for most waterings.

You probably don't need to supplement with Ca and Mg. There is a good amount in your water, and pH is in a decent range for some absorption.

In the US it is recommended not to give water to infants if the nitrate is above 10mg/l.

[bogdan]

Thank you for the good news. I used this water with no ill effects until now, perhaps only some carbonates on top of the media once in a while when I got lazy. So good to know that I don't need to haul distilled water or use that much my R/O unit which I despise using.
The value in German hardness scale corresponds to 320 ppm (I imagine this is what you are using)

Yes, the nitrate is 23 mg/l which is quite a lot, we are in an agricultural region.

Thanks