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do you use RO water?
- Thread starter jocat
- Start date
Hello,
I’m a relatively new grower. I use pH corrected tap water, with some of the worst tap water in the nation (ec .7 to .8 out of the tap). So far no issues, I’m growing in soil though with dry amendments, so I don’t need to push crazy high ec like what’s used in some soil less scenarios. I use nitric acid to correct the pH during veg, and either phosphoric or citric acid during flower.
I’m my opinion, it also depends on your water chemistry. Mine has tons of Ca and a fair amount of Mg. So, I never have to supplement for either of those. I too have though about RO, but right now I’m content.
There are probably no two tap waters exactly the same. What works in one area may not be the same in another due to percolation.
Jocat you are on the right track friend. RO water is the best water for growing cannabis because of its stable nature. RO is the same every time you use it and so the plant can adapt to the water without swings. However, when using RO water one needs to fortify it with a little cal-mag before using. In the garden I'm growing now I put 6 ml of cal mag into 5 gallons of water every time I use water.
When one uses water that has less than 100 ppm and uses a pocket pH meter with it, he can get false readings. I never trust pH meter readings when the water ppm is below 100. pH meters use electronic conductivity and when there's nothing in the water there's no conductivity. So when using RO add a little cal mag to stabilize it before adding fertilizers.
When one uses water that has less than 100 ppm and uses a pocket pH meter with it, he can get false readings. I never trust pH meter readings when the water ppm is below 100. pH meters use electronic conductivity and when there's nothing in the water there's no conductivity. So when using RO add a little cal mag to stabilize it before adding fertilizers.
amanda88
Well-known member
its fine so long as you add your own magnesium supplement (calmag) once or twice during the grow, many growers I know use a mixture of 20% tap water for that extra mineral bite..lol
BuckeyeGreen
Well-known member
I use RO water and I never add cal mag. You don’t have to worry about your ph meter being made to give you a false reading. You are not taking a reading of plain water anyway. Oh and by the way the ph of RO water is seven. You take ph readings after you add nutrients to the water and then take a reading. Correct ph as needed with ph up or down.
I use Dyna Gro Foliage Pro and it is a complete nutrient formula. I’ve never had cal mag issues. RO water is great because you do not get mineral overload in the media. Many problems I see in the photos of others that I see having trouble is because of nutrient overload which then creates nutrient lock outs.
You will really enjoy using RO water. Using it eliminates many grower problems. Mix in your nutrients, correct ph and as as long as you are not overwatering, over feeding or under feeding the nutrients, you will have no problems. I use one teaspoon of the Foliage Pro per gallon, ph to 6-6.2 and use that from early veg. all the way through week 6 of flower every time I water and then use only water until harvest. I don’t have any problems the whole grow.
Good luck.
I use Dyna Gro Foliage Pro and it is a complete nutrient formula. I’ve never had cal mag issues. RO water is great because you do not get mineral overload in the media. Many problems I see in the photos of others that I see having trouble is because of nutrient overload which then creates nutrient lock outs.
You will really enjoy using RO water. Using it eliminates many grower problems. Mix in your nutrients, correct ph and as as long as you are not overwatering, over feeding or under feeding the nutrients, you will have no problems. I use one teaspoon of the Foliage Pro per gallon, ph to 6-6.2 and use that from early veg. all the way through week 6 of flower every time I water and then use only water until harvest. I don’t have any problems the whole grow.
Good luck.
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goingrey
Well-known member
Seems like it has a "guaranteed" (at least) 2% calcium and 0.5% magnesium.
Thanks, Buckeyegreen that's very helpful. You sound like my kind of grower. Also, a big difference between coco and peat substrates when it comes to needing cal mag. as well, and the type of nitrogen will play a big role in the need for cal mag. as well.
BuckeyeGreen
Well-known member
I’m sure that is the case about coco and I should have specified the type of media used. I make my own soi mix of 5 parts composted bark fines, 1 part peat and one part perlite and corrected with dolomite lime which let rest for at least two weeks before using.
Super fast draining media that is nearly impossible to over water unless you let the pot sit in a catch tray full of water after watering for a long period of time. Water it, get a small amount of run off and you’ll never overwater. You may have to water more often than with normal soilless mix like Pro Mix which I used for years and loved.
As far as coco goes I have almost no experience using it and can’t knowledgeable comment on at all. I’ve often been intrigued by coco but when I got into growing coco was beginning get used more successfully but a lot of people struggled mightily when trying to use it. I needed to keep it simple so I avoided it.
I‘ve seen a lot of people use it very successfully so I need to give it another try. So yeah, don’t take my advice and apply it to coco because I don’t really know anything about how to grow in it. Does coco make it harder for plants to uptake cal mag and why is that the case if it does? Eager to gain that knowledge.
What are the benefits of using coco over a soilless media?
goingrey
Well-known member
Coco holds on to some of the cal and mag yeah so the plant doesn't get all of it.
Main benefits are that it's cleaner to prepare indoors none of the dust getting everywhere and how you can water heavier without drowning the roots as coco also holds on to oxygen. Also the dry bricks take very little storage space.
BuckeyeGreen
Well-known member
The benefits you get from coco are what I’m getting from my 5-1-1 mix. My materials require more storage but I store all of it on a couple shelves on a shelving rack in the garage. I make about an 8 cubic foot batch in about ten minutes in the garage and clean up takes about 5 min. I water down the perlite in the bag outside for almost no dust.
I store it in a couple of large totes, also stored on lower shelves on the rack. You can scale it up or down to suit your storage situation. Very cheap to make too. I make about 8 cubic feet for about $18.
I store it in a couple of large totes, also stored on lower shelves on the rack. You can scale it up or down to suit your storage situation. Very cheap to make too. I make about 8 cubic feet for about $18.
goingrey
Well-known member
It's not magic yeah just one option that works. Forgot one benefit which is only when comparing to peat and it's the bog preservation aspect.
BuckeyeGreen
Well-known member
Yes I’ve thought of that and maybe using coco in my 5-1-1 mix in place of the peat, which is only about 15% of the total mix. Now that I think about it I would like to try that. The dolomite lime I use to correct ph in my mix might be something I’d have to look into if I substitute peat with coco. I’d still need it to correct the bark fines but coco probably doesn’t need it or does it? I wonder if I’d now need to add some cal mag. Probably proceed as normal with the change over and watch the plant.
goingrey
Well-known member
Coco is not acidic like peat and doesn't need the dolomite lime yeah.
The main difference in coco fertilizers against general ones is that they have extra cal and mag. If you want to keep using the same fertilizers you may want to add some.
BuckeyeGreen
Well-known member
Thanks for the advice. What coco fertilizer do you like?
I may not need to switch fertilizers since the coco part would only be 15% of the mix but it probably would be a good idea. I still think I’d start with the Dyna Gro and see how it goes. I need to see if Dyna Gro has put out info. about using their nutes with coco. I know they have a Mag Pro product.
I may not need to switch fertilizers since the coco part would only be 15% of the mix but it probably would be a good idea. I still think I’d start with the Dyna Gro and see how it goes. I need to see if Dyna Gro has put out info. about using their nutes with coco. I know they have a Mag Pro product.
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goingrey
Well-known member
I have only tried AN Sensi Coco so far. Seems to work fine.
BuckeyeGreen
Well-known member
I just now contacted Dyna Gro and I left a message asking about using their nutes in coco. I’ll let you know what they say.
jocat
Active member
Man this community is awesome, so much great information, the advise on PH is good to know, I use a blue lab ec meter & never even considered the ph meter to be reading an electrical charge, but of coarse. and reading PH after nutes are mixed...simple obvious but not always done..One other consideration that has come to light in the Oregon recreational cannabis market testing requirements, labs are required to test for the presence of low levels of heavy medals, another positive for RO it is the only 100% consistent way to be sure you can meet these requirements which at the end of the day im glad to know, many people think they have pure water sources but the unfortunate truth of many wells, springs & open water sources is contamination...this aint the world I grew up in in the 60's drinking from the hose...not anymore..
pH is neutral with coco and peat will fall into a low range and need a buffer.
BuckeyeGreen
Well-known member
I also have to buffer my soil for the majority of the material, which is composted bark fines. Not using the peat would probably require that I use less lime but I still have to use it.
