Water with RO water

drew425

Active Member
I just bought a small Reverse Osmosis system to purify my water. Im wondering if I should be adding anything to it before I water. Thanks
 

hotrodharley

Well-Known Member
And I will wager the minerals most present in his water that he will remove - calcium and magnesium along with dissolved lime. All beneficial to plants.
 

Moldy

Well-Known Member
Do garden centres sell any sort of Cal/Mag in any form together or seperate? My local grow shop does not have it
Dyna Gro has a supplement you buy over the net called Mag Pro. Until then try to find out what is in your tap water. Mine is like 400 ppms of minerals but I use RO water and add back about 1/5 of tap water along with my Cal/Mag IF I don't have my soil cut with dolomite. Adding back some tap water will buffer the ph in some instances keeping it from going to low. My RO water is a ph of 7.0 but will drop rapidly when adding nutes but with some tap water it holds around 6.5.
 

drew425

Active Member
Dyna Gro has a supplement you buy over the net called Mag Pro. Until then try to find out what is in your tap water. Mine is like 400 ppms of minerals but I use RO water and add back about 1/5 of tap water along with my Cal/Mag IF I don't have my soil cut with dolomite. Adding back some tap water will buffer the ph in some instances keeping it from going to low. My RO water is a ph of 7.0 but will drop rapidly when adding nutes but with some tap water it holds around 6.5.
Excellent idea. I was wondering why I watered with RO and when I checked my PH levels they were all at 7.0. I guess thats still not too bad. I don't check the run off though I just use a meter right in the soil usually when I think its time to water. My meter checks moisture, temp, and ph.
 

Moldy

Well-Known Member
I've heard checking the runoff isn't a good idea. And that meter you have isn't accurate as I have one of those too. The light meter on it isn't bad for comparing intensity of light sources but but the others (moisture and ph) just don't get accurate enough. You can get a cheap ph meter for around 40 bucks or go with liquid color coded thing for about 10 bucks.
 

intenseneal

Well-Known Member
I have a Ph pen I got off Ebay for cheap and it works great, just as good as the $200 Ph probe on my reef tank. You will want to ad calmg as said with RO water. You will need to increase the Ph with RO water not decrease it. A decent RO unit will bring the TDS in water down to around 5-30ppm stripping all the minerals from the water and thus lowering the Ph.
 

Doobius1

Well-Known Member
My tap water comes out at over 400 ppm. My RO system gets my ppm down to 50. I add tap water to the RO water to bring it back up to around 125 ppm before adding nutes. This does 2 things. 1- gives my plants neccessary micronutriants and 2- keeps me from using too much ph up or down. I grow hydro and this will bring me pretty close to my desired 5.8 ph level.
 

hotrodharley

Well-Known Member
So watering with tap water is actually better for the plants?
Let me put it this way - I have been growing since 1964 and if I haven't tried it I want to hear about it so I can. Water is the easiest thing to manage for pot. Tap water supports all other forms of life - animal and plant - so why would pot be any different? Yes it can be made optimal or close to it but why?
 

hotrodharley

Well-Known Member
I have a Ph pen I got off Ebay for cheap and it works great, just as good as the $200 Ph probe on my reef tank. You will want to ad calmg as said with RO water. You will need to increase the Ph with RO water not decrease it. A decent RO unit will bring the TDS in water down to around 5-30ppm stripping all the minerals from the water and thus lowering the Ph.
You're way wrong about the pH.
 

WhiteRooster

Active Member
After running water through a RO filter I like to let the water sit for at least a couple of hours or overnight with an air stone and pump to add oxygen back into the water that the filter removes.... Then right before I water I balance the pH with down and up to where I need to be for my growing medium
 
My tap water comes out at over 400 ppm. My RO system gets my ppm down to 50. I add tap water to the RO water to bring it back up to around 125 ppm before adding nutes. This does 2 things. 1- gives my plants neccessary micronutriants and 2- keeps me from using too much ph up or down. I grow hydro and this will bring me pretty close to my desired 5.8 ph level.

I just got my RO installed its coming out around 90ppm but its getting lower, im gonna go with what you said and add some of my super high tap water (750ppm) to it instead of buying cal mag
 

Doobius1

Well-Known Member
Let me put it this way - I have been growing since 1964 and if I haven't tried it I want to hear about it so I can. Water is the easiest thing to manage for pot. Tap water supports all other forms of life - animal and plant - so why would pot be any different? Yes it can be made optimal or close to it but why?
Holy crap Hotrod I was still poopin in my diaper in 1964
 

hotrodharley

Well-Known Member
Holy crap Hotrod I was still poopin in my diaper in 1964
Most here weren't even a glint in their young daddy's eyes in '64. I was a high school sophomore. One of about 25 guys who smoked pot in my school. They called us "heads" and we were REALLY looked down on. The US/MX border. A rich white kids high school. Public but between ritzy places. I hated it. The kids in Segundo Barrio, right on the border literally? Those griffos smoked a lot of weed. Scored a lot of good smoke down there.
 

hotrodharley

Well-Known Member
My dad was a blacksmith and ranch kid, I grew up on that ranch until high school. I know water. Good water and bad water. Brackish water and plain poison wells. City tap water? A fools errand trying to let chloramines dissipate. At the levels present it will not harm the beneficial microbes in soil after minimal soil penetration.

"
[h=2]How about using chloraminated water on ornamental plants, vegetables or fruit and nut trees? Will beneficial soil bacteria be harmed?[/h]The small amount of chloramines should have no effect on plants of any type. Beneficial bacteria will generally be protected by the soil in which they live. Chloramines will be removed by the high chlorine demand in the soil."

http://www.amwater.com/ilaw/ensuring-water-quality/chloramination-faq.html#q21
 

drew425

Active Member
Let me put it this way - I have been growing since 1964 and if I haven't tried it I want to hear about it so I can. Water is the easiest thing to manage for pot. Tap water supports all other forms of life - animal and plant - so why would pot be any different? Yes it can be made optimal or close to it but why?

good point
 
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