4 weeks 2 days into WW with cal-mag deficiency??

Ok new thread.... I have been investigating and reading a lot lately on plant issues and problems. This stared when I noticed the yellow and rust-brown spots forming on the leaves in large areas. In the past week I have determined the pics here are signs of a cal-mag deficiency.


I have extremely hard water in my town. So hard that sand drains from hot water heater, and even uranium is present. I have been using regular tap water for the past 5 weeks. Prior to that I was using RO water which is fed by a water softener. Looking in my notes, 3 weeks ago I noticed small spots and a light green appearance to the large fan leaves. That week I trimmed most of the larger fan leaves off in prep for flowering, and I forgot all about it. My substrate also contains a lot of coco, and if I am right Cal. and Mag. deficiencies are pretty common unless you add dolomite lime or a cal-mag supplement.

I cant show you guys any more proof that I am not dealing with spider mites here but in fact a cal-mag deficiency. My other plant is beginning to show all the same signs and i am getting worried. So I will make this as clear as possible...

Is it too late to correct Calcium and Magnesium deficiencies in my White Widow, from seed, in soil, under a 600W HPS, at 4 weeks 2 days into Flowering?

Here is the quote I am basing my knowledge off of? I have found other cases and info that helped me decide, this one just explained it best.

Full thread...
http://forums.cannabisculture.com/forums/ubbthreads.php?ubb=showflat&Number=87353

{Anonymous #87358
"Hard water depends on what makes it to be considered hard,high level of calcium,mag,potassium,sodium,others.burnt leaf tips can be many things, high temp/low humidity and over fertilization.rusting of the leaves is another mineral deficiency.wilting can be a plant asking for water, or a deficiency,one very common problem is sodium levels, levels above 50 ppm of sodium and the plant will overload with salt and forget about the rest, this can cause wilting, rusting,sodium encrested leaves,purpling stems.just because it can take up nothing else,even if you water is relitively hard ,flushing with plain water(the same stuff) every 3-4 weeks will probably keep you out of harms way.if you use distilled water or RO water you have to know how much of all the chems you need to grow at each stage, tap water may contain some minerals that you do not provided in you fert list causing a plain old underfert prob.about the only tap water that you should never used is salt softened(water conditioner) for obvious reasons. peace"}

What's your runoff PH?

run off is 6.8 (with just water not nutes)

If your water is that hard you're probably locking out Mg, Mn, Zn ... the remaining divalents.
I had a WW seedling absolutely not thrive on tap water hydro ... went into soil in abject defeat. Imo a part of the problem was chloramine in the tap water. Are you sure you have no chloramine? cn

Do u use soil or hydro growing !? Its very important chart u have to water with ....

They are in soil.

Is that greenhouse's ww?

I do gh's and they are Nitrogen HOGS, especially in early flowering.

I do not know what is GH WW? a strain i assume?

i would agree u have a mg def. the question is what is causing it. i think most likely its lockout from salt buildup from the hard water. try flushing, then add mg supplement as recommended along w whatever nutes yr using. use ro water if possible. imo, the hard water is locking out yr nutes. also imo, dont trim off fan leaves except maybe the very bottom ones to allow for air flow beneath the canopy. yr plant needs fan leaves for many reasons, mostly photosynthesis. hope this helps

I am about 33 days into flower and having some calmag issues as well. I am using a soiless mix. I have resently started using botanicare cal mag plus adding it to every watering at a rate of 2 teaspoons per gallon. My water comes in at .3EC after I add the calmag it jumps to 1EC and then I add dutchmaster gold and bring the total up to 2.2EC. So far it doesn't seem like its spreading.

I used to adjust my water to 6PH but was told thats a little low so now I am adjusting it to 6.3 to 6.4.