Can u tell what is wrong? (calcium?)

I have 5 Cheese strain cannabis plants they are all about 7-8 weeks into flowering. I noticed some brown spots forming on 1 of them. Slowly but surely it was happening again to another 1 of my plants, and then another. So 3 of them have these brown spots/curling. It almost seems like there catching it from one another? But calcium deficiency happens from within the plant ? U can’t catch it from another plant can u? From the research I’ve done I believe I have 3 calcium deficiency plants? I went to my local hydroponic store and purchased some calimagic. It seems as soon as I gave it to them I started seeing more and more leaves with brown spots& curling.
So this is where I need your help. By looking at them can u tell me what’s wrong with them?

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I believe that this is your problem.
I think that this pic s what’s wrong with yours.

Manganese (Mn) Micronutrient and Immobile Element

Manganese Helps enzymes break down for chlorophyll and photosynthesis production, as well as it works with plant enzymes to reduce nitrates before producing proteins.

Having plants that are deficient in manganese can turn the young leaves into spotted (mottled) yellow and or brown areas on young leaves. Dead (Necrotic) yellow spots form on top leaves, while the lower older leaves will or may have gray specks and or spots. Symptoms can include yellowing of leaves while the leaf veins can stay green. Can also produce a chequered effect. As the plant gets newer growths the plant will seem to grow away from the problem, that’s why the younger leaves may be unaffected. On the top of the leaves, brown spots can appear. While the severe areas of the leaves turn brown and wither. Parts Affected by a Manganese deficiency are: Young leaves.

Too much Manganese in the soil will cause an iron deficiency. The blotchy leaf tissue is caused by not enough chlorophyll synthesis. Your plants will seem to have very weak vigor caused by the excessive amount of manganese.

Problems with Manganese being locked out by PH troubles

Soil ph of over 6.5, High iron soils, Low nitrogen Soils, Dry weather
and compacted soil.


Manganese gets locked out of soil growing at ph levels of 2.0-5.0
Manganese is absorbed best in soil at a ph level of 5.5-6.5 (Wouldn’t recommend having a soil ph of over 7.0 in soil) anything out of the ranges listed will contribute to a Manganese Deficiency.

Hydro and Soil less Mediums

Manganese gets locked out of Hydro and Soil less Mediums at ph levels of 2.0-4.5
Manganese is absorbed best in Hydro and Soil less Mediums at ph levels of 5.0-5.6 (Wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a manganese deficiency.

Solution to fixing a Manganese deficiency
Foliar feed with any chemical fertilizer containing Mn., or mix with water and water your plants with it. Any Chemical/Organic nutrients that have Manganese in them will fix a Manganese deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Other nutrients that have Manganese in them are: Manganese chelate, Manganese carbonate, Manganese chloride, Manganese dioxide, Manganese oxide, Manganese sulfate, which are all fast absorption. Garden Manure, Greenssand are both good sources of manganese and are medium/ slow absorption.
Now if you added to much chemical nutrients and or organics,( which is hard to burn your plants when using organics) You need to Flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it,you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

I hope this helps. indoor and outdoor growers in killing and preventing Powdery Mildew. Outdoor growers can use Organics List below to help prevent Powdery Mildew of starting, even after it has started using anything below will help kill it off. (Note: When using chemical and or organic control methods, do not spray the buds, and for health and safety reasons, stay away from spraying around the buds if all possible.)

Plant Shield
Garden Disease Control
Fungicide containing Lime, Sulphur

JMS Stylet Oil
Saf-T-Side Spray Oil
Sunspray Ultra-Fine Spray Oil
Neem Oil
Neem 2
Safer Garden Fungicide
Concern Copper Soap Fungicide
Guardian Angel
Serenade Garden Disease Control OMRI
Safer 3-in1 Garden Spray OMRI
Sulfur Vaporizer
Garden Sulphur
Sulphur Burner
Sodium Bicarbonate
Mother Nature’s Karanja Oil
Concern Copper Soap Fungicide

I use the SM-90


What is that white stuff on it?

Picture are too blurry to make a good assessment of the issue. I don’t think it is Manganese issue.

I am concerned with hacked off leaves. Try to take more clear pictures. Thanks