Is my water good right from the tap?

[florianradke]

I live in an area with overall hardness below 75 ppm, pH between 6.5-7.5. With specific parameters attached below as an image.

Am I one of those lucky few who can use tap water straight as is? Or should I be concerned about the sodium levels, among other things.

Thanks!

FR

[Edit: just noticed the attached image is not clear enough to read. Sodium is at 20ppm]

[estación seca]

That will be fine. Be sure to flush your plants at each watering and not just drizzle in a little.

[Lil Duck]

people use tap water at 250 ppm with no problems, as long as you aren't growing delicate cloud forest plants like pluerothallids or former sophronitis, 75 ppm should be fine. The more delicate sp need water under 50 ppm and ideally under 25 ppm.

Edit : left out a piece

[florianradke]

I do actually have one pleurothallis, which is doing fine and has put out two new leaves.

Surely there must be some point at which - way below 25 ppm - nearly all anions and cations have been removed (true deionized water or ultra pure water) where root membranes can no longer function...

I mean, rainwater is certainly something to aspire to, but sometimes I wonder if rainwater is confused for pure water. Rainwater is not actually pure water - I'm not aware of any source of water on earth that is. But it does bring up what it is exactly we mean by "pure" water. For one thing, surely there is no single standard for "pure" water. It brings to mind questions about whether - and if so - why - rainwater in different regions has more or less minerals in it. And how important - or not - tuning ones water supply to match the bioregional rainwater characteristics of a given species is.

Unless by pure we mean molecularly pure diatomic hydrogen - completely absent of all organic and inorganic solutes... But I imagine but don't know for sure that, just as humans cannot safely drink consume deionized water without causing an electrolyte imbalance, plants cannot safely absorb deionized water - or - water that has been "purified" so far that mineral ion transport into and out of roots grinds to a halt.

[estación seca]

Pure in colloquial horticulture usually refers to reverse osmosis, rain or distilled water.

[MateoinLosAngeles]

Your chart is hard to read but if I'm not mistaken the numbers on the left under the MCL and MCLG columns are actually the maximum allowable by the EPA and included as reference. Your water read would be under the "detected levels" columns, which shows your sodium level to be actually 4.3ppm.

I don't see the levels for Ca or Mg but if I'm reading the chart correctly your water is extremely pure, which is frequent in the Northeast where most tap water is considered generally soft or very soft. Apparently the large non-porous bedrock located in these areas is a contributing factor. I also believe Massachusetts has the purest water in the Northeast.

If I'm reading the chart correctly I would treat your water almost as if it was RO and use the appropriate fertilizer.