Reverse Osmosis

Hello everyone,

Ever since seeing calcium starting to build up on a lot of my trees nebari and having heard and read different inputs about water quality/pH levels etc. ive been looking into RO systems. Ive got very hard water here in my garden in switzerland.

Ive found quite a few products for inhouse/under the sink RO but systems for permanent garden use only very few.

One system ive found is the Power Grow 500.

Has anybody else got any experience with this product or other recommendations?

Another tip i got to lower the calcium would be to let the water stand in a container for one to three days so that the calcium settles on the bottom of the canister. But i very much doubt the “science” behind that but maybe somebody here can confirm or deny this?

Thank you all for any kind of help!

Have a great day,


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RO water has nothing in it. View it as “empty” water. if your water is truly that hard, blend it with the RO. don’t use RO straight as what it will do is strip out minerals from your bonsai soil and create that aluminum toxicity that you hear Ryan talk about. Water wants things. think of RO water as being very hungry for what is in your soil and your hard water as being full. Hard water has its disadvantages as you get a lot of hard water deposits on your pots and it plugs sprinkler ports. the idea of letting it settle might work if some of it is evaporating and your mineral content is already at saturation at the start so some has to drop out of solution. Otherwise not a good idea in my view. if your water is chlorinated, letting it sit will remove the chlorine. I think a better start for you is to watch some of Ryan’s learning sessions on Apical and possibly get your water tested before you start in with the “witchcraft”. they can help you. also if you are not strong in chemistry, which I suspect, get yourself some reading material on ionic chemistry to better understand water. The best way to kill trees is to jump in and do things without a lot of thought being put into it. For background, I own a laboratory and have access to RO water and don’t use it other than for blending. look at Ryan’s sessions and what Apical has to offer and maybe at least consider some of that before you invest in an RO system. There is no magic in any of this. I even have my own testing capabilities and am considering sending things to apical to see what is going on in my trees as our expertise is not horticultural like Apical.

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Thank you very much Cheryl for your reply! Ive already listened to all the podcasts with David and am just finishing the podcast about soil science. Ill definitely check out any video material in the video library.

Isnt distilled water the water void of all minerals, electrolytes and other soluble parts? To my understanding RO water has a certain amount left seeing as some parts still can pass the membrane.

How do you then use your RO water exactly?

the answer is it “depends” it depends on the quality of your RO system. RO systems use a series of cartridges to remove the minerals from the water starting out with a rough cartridge that removes most and then a series of additional ones to remove more and more out of the water. I do not have an RO system at my house nursery as I own a laboratory with a high quality system and just bring water from there. I do not know how much a system that nurseries may use takes out of the water. I imagine not as much as a laboratory system. I imagine some minerals remain but so trace as to be unimportant to you. what happens when you water has so little in it though is that it strips minerals from your soils as it goes through. what it strips and how effective it is at this depends on the pH of the water. acid pH tends to dissolve minerals more effectively than alkaline pH but there are exceptions depending on the mineral. this is all basic chemistry and nothing that I came up with on my own. Distilled water creates mineral-less water in a different manner by distilling over the water and leaving the minerals behind. depending on the cleanliness of the process and the RO system you are comparing it to one could have more minerals than the other either way. I think if you live in a location where the water contains a lot of minerals like many of the cities in AZ, or in the midwest where water is coming out of limestone aquifers you may want to invest in or have access to some RO water to use for mixing with your pest control products, washing leaves, cleaning pots, or occasionally even watering your trees to remove a salt build up. Some trees like an emptier water that is more similar to rain water - ie azaleas. I wouldn’t fixate on whether it is highly pure RO or distilled water. you just need it to be fairly mineral free. If you know chemists that work in laboratories they can probably provide you RO water from their systems if you have some carboys to put it in. cheapest way to get high quality clean water. If you are really interested in this topic, and are not a chemist, get some books on ionic chemistry. A lot of what is being practiced by apical is ionic chemistry with an understanding of horticulture. I am a chemist and plan on listening to that again as there is a lot to absorb in that session.

Well thank you very much for the extensive reply! Ill look into it some more :smiley: