tap water versus filtered water

[camille1585]

It depends on the filters too I guess, but if your water is quite hard to begin with, the filters do remove calcium, but I don't think it removes it all. Of course, I may be talking utter BS here since i haven't used a filter since moving from the states 10 years ago. But if that water still leaves residues on the leaves, it's obvious that it was not all removed. Filters may filter things, but they don't make distilled water.

[Ray]

... Currently I use water that i boiled over in a kettle. That gets instantly rid of all chlorine and some of the minerals as well.

Boiling does not remove any minerals. In fact, because you are losing water to accelerated evaporation, you're actually concentrating them in the water that remains.

Think about distillation: you boil water and then condense the vapor, giving you pure, mineral-free water, because none of the minerals evaporated in the first place.

[siannevo]

So after much research, I found that a lot of it comes down to a person's individual water. One of your guy's water could be much better than mine, so the first thing to do would be to test one's water levels. A cheap way to do this is buy a EC/TDS meter. It is not super accurate, the more accurate way is to get the City (if you have city water) to do a reading for you. If it turns out your water is horrible, then its best to either buy distilled water and mix in equal parts of your tap water or use rain water (but for some of us we dont always get a lot of rain, I may live by the beach but it rains here maybe one month out of the whole year.) A lot of people do neither and just wait to see if something happens to their orchids before they take an initiative, and then its trying to find out if its the water or the fertilizer. Reverse Osmosis sounds awesome, but only for super serious collectors who have many many orchids...but if this is not the case I would love to know peoples RO experiences. I only have six orchids, and if I hit 35 perhaps I will think about this option, but it seems to have some severe drawbacks. There is a lot of wasted water, it can corrode your pipes, and you need to dilute it with fertilizer. So for the moment RO doesnt seem like such a good idea for someone who rents their apartment and doesnt have an extensive collection. So far I have not seen any salt problems from my water, but I did notice a little bit of a salt problem from a feed I was giving to one of my plants, so Zdenglan you might also want to check your fertilizer, but you seem to have found a way that works for you. And that is the number one thing that most materials I read said...you have to find the way that works for you and your orchids in whatever location you are living in.

Thanks everyone for your feedback. Now its down to trail and error...eek.

[RosieC]

Ok, I finally remembered to take a look at the details of these water filters.

As I said before when I hear 'filtered water' what I think of is these 'Active Filters' which are very common in the UK.

Brita make the ones I have but there are other makes that are very similar in the UK.

They have charcoal and other stuff in them and according to the details they remove...
Chlorine
Limescale
Aluminium
Heavy Metals (like Lead & Copper)
certain pesticides and organic impurities

As a side effect they add...
Silver
Potassium

They state on them that the water must already be 'from supplies which have been tested as safe to drink'.

Well if it's potasium and silver that they add then I would guess they are safe to use on the plants. But are any of the heavy metals they remove actually good for the plants?

[RosieC]

Agreed, if there are white residues it sounds like calcium and if the water was first filtered it obviously did not remove it (or all of it).

Also agreed, the results of any filter will never be like distilled water.

Oh well, don't think I can answer if filtered water is good or not... it seems it depends

[brush]

For my orchids I fill my water jugs with plain tap water and leave the cap off so the chlorine will evaporate overnight and it will be ready to use when I need it . I think if you have clay pots for your orchids some of the minerals from the water and even from the fertilizer that you are using for your plants will build up on the clay pots over a period of time . I just moniter that build up and scrub the pots when necessary to do so .

I think also it is important to let your water rest to evaporate the chlorine , which the orchids don't like . Having your water you use for your orchids at room temperature is a bonus for your plants too because it does not shock them when you water them.

[Zdenglan]

If i am to nitpick then if a kettle is boiling for 10 seconds then the evap rate is negligeable and concentration of minerals is not getting any higher. If you have anything but soft water then you must have noticed the coating of the kettle heating element after some time you have been using it. In my reckoning that means that the heating element actually attracts mineral salt ions from the water (as they don't stick to the plastic parts of the kettle or your watering can for that matter). Anybody any thoughts on that?

BTW My partner has done advanced physics and have just said this: When the element generates heat, water's turned into steam and generates a bubble at which point the calcium ions have a chance to attach at the heating element in form of salts. Now it depends on the overall temperature of the heated water - untill the very point the entire contents of the kettle are boiling the bubbles that form at the vicinity of the heating element deposit their calcium and rise upwards where the temperature is lower that 100 C. That results in colaps of the steam bubble that turns back into liquid (that's why kettles make the humming noise) . So it seems that it is either 'boiled water is ever so slightly less calcareous than the tap water' or 'the processes cancel each other out but it gets rid of the chlorine quicker than leaving the water stand overnight'. Anyway I'm probably going too much in depth here. Time for bed

[Ray]

Actually, to be scientific about it, the evaporation rate from boiling water is significantly greater than for room temperature water, so by default there will be some concentration of the dissolved minerals. Whether that increase is of any harm is another issue altogether, and I suspect the answer is likely "no", unless your starting water is really hard!

[Zdenglan]

I suppose you're right. Another thing I read somewhere was to soak a muslin bag full of sphagnum peat in your watering can overnight. It's supposed to slightly acidify the water by cation exchange. Any thoughts on that Ray?

[breeindy]

Hi i don't know much about water quality but i bought a rain water tank when i starting getting a few orchids just so i wouldn't have to worry. Ive also heard that rain water lacks something that orchids need and can be added by using certain fertilisers for rainwater. anyone know anything about this? Salt build up is the biggest killer isn't it? and tap water, bottled water and fertilisers have it. I flush my plants every few waterings from the top to flush any salt build ups. You can sometimes see these build ups of white around the top of the soil in bad cases.