If you haven't had problems yet, keep doing what you are doing.
The city sewer and water department should have a website where they post the actual test results on your tap water. Look at the TDS number.
If you are on a well, and suspect your mineral content is unstable, you are better off buying a meter. The cost of testing through a private lab can be high, and if you think you will need to have your water tested more than once, it's cheaper to get a TDS/EC/PPM meter.

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"Multiple pieces of anecdotal evidence do not equal scientific fact." -Rhizome
"If the Queen Bee ain't happy... the hive isn't happy!"-Dutch Pimp
http://boards.cannabis.com/basic-gro...e-harvest.html<-It's a grow guide! Enjoy!
http://boards.cannabis.com/plant-pro...hy-how-do.html <- all the boring stuff about soil chemistry you never wanted to know
http://boards.cannabis.com/grow-log/...ml#post1837597 <-how to make canna caramels
http://boards.cannabis.com/grow-log/...ml#post1820481 <-illustrated cloning guide permalink
Contacting Her Dankness: stinkyattic at hushm4il-please use the same discretion you do on the boards, thanks.
I don't claim to know the first thing about growing anything; hell, I can't make a Chia pet sprout.

Out here in the country we have agricultural extension office in each county. They will test water for free. I assume there is one in each county in the USA.

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I disagree about the calmag. I've never heard of it and therefore never used it. I have discovered that using r/o water with Advanced Nutrients Sensi Grow/Bloom works out perfectly in a hydro setup and that is all I ever use. I never have to check ph or ec and have had much success. Lucky I guess.

Cal-mag plus will drop your water ph even at 2.5 mls per gallon and I don't even know how many ppm's that will get you to, so the more you need the more it's going to drop your water ph.

I just collect rain water than run it through a micron filter works perfect!

Yes You are.

It is a fact that cal mag is necessary for optimum growth. Ask any commercial or professional grower.

While I am at it. Someone asked about amount to use.

For seedlings; You might add 3ml per gallon. The bottle says to use 5-8ml.
I generally never use 8ml unless late in flower week 4-7, before flush.

You have it correct bitemybud, first that's it necessary and second ask any commercial or professional grower. Commercial growers are a great source of information and while none will entertain mj questions, what they do and how they do it, is applicable to what you grow.

Also note; cal/mag is NOT required if you use Pro-Mix, it contains dolomite lime. When dolomite breaks down it provides calcium and magnesium so it is already in the container. It is one reason professional greenhouse operators use it, one less item to meter into thier RO water.

Hello, people!

“it is a fact that cal mag is necessary for optimum growth. Just ask any commercial or professional grower.”

Well, yes, that's true, but I am a professional grower and I don't use any calcium or magnesium supplements because I don't have to. That's because I use a nutrient that already contains more than adequate amounts of each and I run ph at levels that allow for sufficient uptake. In the greenhouse hydro industry growing tomatoes with drip irrigation in perlite culture many operations use bulk nutrient preparations that are dry and come in two parts. One part contains everything but calcium nitrate, the other part is calcium nitrate. They keep them separate to prevent magnesium sulfate and calcium nitrate from interacting. Just as the gh flora series, techniflora nutes and many others do, liquid or dry. The one part flora nova gets away with everything in one bottle as it is a colloidal suspension that separates during storage, thus preventing the interaction. However, there are many nutrient packages that don't contain sufficient cal-mag. Pure blend pro is a classic example. You absolutely must use cal-mag with it to avoid disaster.

I am currently using maxibloom for flowering. It is a one part product that does not have any reactions until you put it into solution in water. It contains ample amounts of cal-mag.

The calcium/magnesium deficiency most folks run into eventually using hydro nutes is caused by ph being maintained at levels that don't allow for decent uptake. Not by the nutrients being low on either calcium or magnesium.

I know I run the risk here of opening up a whole can of worms on proper cannabis hydro ph, but here goes anyway.

Most of the ph charts you see are incorrect or misleading. Most would have you believe that if you don't run at a specific ph you are running the risk of lockout of one element or the other. Some depict uptake of elements at different ph points that don't even overlap with their recommendation for ideal ph, usually at around 5.8.

The truth is that there is no such thing as ideal ph and there are no finite points where lockouts occur. Every application is a compromise. However, the 5.8 recommendation is right in the middle of the range where you get the least calcium and magnesium uptake. You are still getting some, but usually not enough. You either have to get above 6.0-6.1 or below 5.5 to get adequate uptake of calcium or magnesium. I believe that above 5.5 phosphorus availability starts diminishing so I start my input solution at 5.2. As nutrients are used and evaporation/transpiration occur the ph will climb. The girls love it and show no symptoms of deficiency.

So, if you are using ro or distilled water and your nutrient shows calcium and magnesium on the label try running your ph between 5.1 and 5.4 for a while and see what happens. I think you will be pleasantly surprised.

If you are using ro water it is probable that you have very hard water from your tap and you decided to use ro water to solve the problem. If your tap water is over 200 ppm at the .5 conversion (milwaukee meters), you probably have too much calcium in your water. The calcium in your tap water plus the calcium in your nutrient solution can add up to an over abundance of calcium. An excess of calcium can cause a magnesium deficiency. You see the mag deficiency first and you think you need more magnesium so you add cal-mag thereby aggravating the situation. You can run into a similar scenario adding epsom salts (magnesium sulphate) to your solution. Too much of one nutrient can cause problems with uptake of another.

If your tap water is below around 150 ppm and doesn't contain more than 70 ppm calcium (only a water analysis can tell you this) try correcting ph to 5.2 for a while. With Ro water, if your nutes show Mg and Ca on the label, try 5.2 for a while.
Or you can blend ro water and tap water in proportions that get your tds below 100 ppm, then try 5.2 for a while.

My tap water is slightly over 200 ppm most of the time, so I blend tap 40%/ro 60% and end up with a reading of around 80 ppm before nutes are added. I chose this ratio because of the ph buffering capability inherent in the tap water mixed with ro at this ratio allows me to get away without using ph adjusters, either up or down. 2 gals tap plus 3 gals ro plus 2 level tablespoons maxibloom gives me 5.2 at around 950 ppm every time. I have visually perfect plants showing no signs excess or deficiency.

Well, I hope this little discourse helps someone be a better grower. Later delta9nxs

Excellent first post delta9nxs! And welcome to the canna boards, I hope to see more posts from you.

You've raised two very important points:

1) everyone needs to check what is in thier nutrients, water, medium and any additives...it is real easy to over do a nutrient element.

2) PH is extremely important to nutrient uptake and the fact that it "drifts" is a good thing, since various elements need slightly different PHs to get utilized.

Thanks for the informative information. (is that redundant?)

I'm using R/O water for my grow. Should I continue to add CalMag when my grow goes into the "straight water" flush mode at the end of flowering?

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delta9nxs and welcome to cancom.

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Hi McToker,

Sorry no one answered your question right away.

Yes you should continue the use of cal/mag during flush, it will help the plant use up any nutes left in the soil, but also any nutes left in its' cells. If your using the cal/mag as directed the amount is so small it will not effect taste. It's just as if you where using tap or decent well water there is just a trace of micro-nutrients in it.

Thanks oldmac. That's kinda the way I was leaning but wanted to make sure.

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50 is the new......... awww, who am I kidding.....

Lord, I'm much too young to feel this damn old ~ Garth Brooks

Our 1st Grow ~ The McTokers go to school or Why it doesn't pay to go cheap http://boards.cannabis.com/grow-log/...-grow-cfl.html

Im confused, If I use tap water and add nutes, it will mess up the plants?

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Currently Building Growroom...

what about reg. bottled water

you most certainly can use nutes with tap water. can you be a little more specific with what you are needing clarification with please?

be more specific. is it spring, distilled?


-shake

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"But, when a long train of abuses and usurpations, pursuing invariably the same object, evinces a design to reduce them under absolute despotism, it is their right, it is their duty, to throw off such government, and to provide new guards for their future security." -Deceleration of Independence

sorry-spring water

you shouldn't need any calmag+ spring water as it contains most of the micronutes that your ladies need. they should get the rest from your nute regimen.


-shake

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"happy trees"

troubleshooting form

"some of my sweets be tight and some of my sweets be fucked up, but all of my sweets gon' blow so killa smoke gets sucked up..." -Bun B

"But, when a long train of abuses and usurpations, pursuing invariably the same object, evinces a design to reduce them under absolute despotism, it is their right, it is their duty, to throw off such government, and to provide new guards for their future security." -Deceleration of Independence

thank you shake

no problem. if you have to used bottled water, i would stick with spring.

-shake

__________________
"happy trees"

troubleshooting form

"some of my sweets be tight and some of my sweets be fucked up, but all of my sweets gon' blow so killa smoke gets sucked up..." -Bun B

"But, when a long train of abuses and usurpations, pursuing invariably the same object, evinces a design to reduce them under absolute despotism, it is their right, it is their duty, to throw off such government, and to provide new guards for their future security." -Deceleration of Independence

So if Im using distilled and the flora series I dont need cal mag?

'Spring water' is a very generic term. Do you know this spring? What minerals and organic acids are in it? How much sodium does it have?
Spring water bottled for drinking often has too much sodium for plants, and not enough minerals. You're better off running distilled + calmag... at least you know what's in there!

Bottom line: Know your water. If you've got no way of testing the EC, then IMVHO... stick with tap water and a soil style of growing...

__________________
"Careful what you carry- 'cause the Man is wise- you are still an outlaw in their eyes" -Steely Dan
"Multiple pieces of anecdotal evidence do not equal scientific fact." -Rhizome
"If the Queen Bee ain't happy... the hive isn't happy!"-Dutch Pimp
http://boards.cannabis.com/basic-gro...e-harvest.html<-It's a grow guide! Enjoy!
http://boards.cannabis.com/plant-pro...hy-how-do.html <- all the boring stuff about soil chemistry you never wanted to know
http://boards.cannabis.com/grow-log/...ml#post1837597 <-how to make canna caramels
http://boards.cannabis.com/grow-log/...ml#post1820481 <-illustrated cloning guide permalink
Contacting Her Dankness: stinkyattic at hushm4il-please use the same discretion you do on the boards, thanks.
I don't claim to know the first thing about growing anything; hell, I can't make a Chia pet sprout.

i stand corrected. thanks stinky!

-shake

__________________
"happy trees"

troubleshooting form

"some of my sweets be tight and some of my sweets be fucked up, but all of my sweets gon' blow so killa smoke gets sucked up..." -Bun B

"But, when a long train of abuses and usurpations, pursuing invariably the same object, evinces a design to reduce them under absolute despotism, it is their right, it is their duty, to throw off such government, and to provide new guards for their future security." -Deceleration of Independence

Never have truer wordz been spoken

my tap water has 35 mg/l of calcium is that pretty high will I still need cal/mag and also what would be the ppm reading for 35 mg/l of calcium

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