Hey guys! Back again with another problem. So Im coming up for 3 weeks now since the flip. A week ago the plants looked fine but some leaves around the middle had brown spots. Now The tops of the plants have started to yellow some what. The shoots are bright yellow and then as you go down the plant they get darker. There is interveinal yellowing so the yellow is on the o/s edges and veins remain green. It looks very much like an Iron deficiency.
With the brown spotting I felt I might be getting a calcium deficiency. Ive realised maybe our soft spring water maybe lacking in Calcium and magnesium. Straight out the spring its about 120 ppm on the EC meter and today was 6.1pH but normally its around 6.4.
So this week I gave the plants some epsom salts in their water and also got some bio bizz cal mag for organic yesterday which I gave them some.
So I'm sure its either a cal/mag deficiency or a Iron deficiency? Common cause should be pH. So I always use our spring water that's around 6.4pH. I'm using plant magic supreme soil charged with frass (ecothrive charge) as a kind of super soil. I recently top dressed with some more charge.
Today I tested the pH of water at 6.1 and EC 120 and watered one plant till I got some run off and then tested that. pH of run off was 5.6 and EC 1000.
I know the run off isnt a reading of soil pH but what do the experienced grpwers think. Is this too low and the source of my problem? Also if I'm completely organic, no salt based feeds, do I need to worry about the EC of the runoff. I'm guessing the Epsom salts, cal mag and Molasses I gave this week are contributing to that reading.
Getting really worried as the buds are just starting to show and I'm worried my plants are going to be wrecked by this. Temps are 26C high and 17 low. Humidity has been high during lights out but just got a dehumidifier in today.
One final thing I've noticed. There are 8 plants in a scrog. 4 in each half the tent. If you were to divide each half into 3 running along the grain of the lights (600w HPS) the third underneath the bulb are less effected by this problem and its worse on the outer 1 removed link This is happening on both sides of the tent? It's making me wonder whether my lights may have been too low? Could this be the problem. They were 40cm above the canpy with A wings and a super spreader. Once I noticed this I've moved them up to 60cm above.
Long post I know but thanks in advance of any replies. Thought my first indoor grow was going great until recently, now I'm panicking!!!
@mrtweed hi mate
as Macky said.. spot on advice right there 👌
cal-mag and Epsom salts both contain high magnesium so usually both aren’t added, just one of other, and not usually to the organic soil. Foliar application way to go as Macky said ..
If calcium and magnesium are not in correct ratio this can lower pH / also lockout nutrition uptake. By adding both one is likey locked out
eg if too much magnesium, calcium becomes unavailable and vice versus
This can also cause brown spots (chlorosis)
doesn’t sound too late to adjust
pics maybe helpful
good luck bro
some epsom salts in their water
Salts in the medium like that can cause issues mate, epsom salts are best foliar fed 
It's making me wonder whether my lights may have been too low?
40cm might be abit low for a HPS mate, it was a good idea to raise, it. 18 inches which is about 45 cm is good. Watch the plant for sign of heat stress at the top.
Considering you're using no salt based nuits, but you gave epsom salts in the medium, i would say this was the cause. Organics likes to have a lot of good bacteria in the medium to break down the food and make it plant available. Its not the same as salt based nuits. When you add salts to an organic medium it can kill the microbes. This is essentially stop the plant eating properly. And will also be the cause of the high EC.
Also, living soil should not be getting any run off mate, any run off is washing out good shit the plant will use, so you may have also washed out the nuits in the medium, and the plant could be hungry.
Have you been getting run off often? And how much epsom salts did you give?
Thanks guys. I dont normally get run off at all. Just wanted to do it a little to get an idea of if pH in the medium is okay. only did it on one of the plants. I believe that epsom salts are okay with organic I think even sub cools super soil recipe has a quantity of it in there. But I maybe wrong. I think I added 2 teaspoons in 5 litres water. each plant had about 1.5 litres water.
That's the first time I've fed with it. Didn't want to foliar as buds are just starting. The chlorosis problem was showing before I fed them epsom salts but perhaps it may e worse now? It's hard to tell.
Should I maybe flush and then reinnoculate with some compost tea and another top dress of charge. I'll take a picture tonight.
The problem started pretty much around the flip nearly 3 weeks back.
Does the lower pH of the run off indicate any problem?
Should I maybe flush and then reinnoculate with some compost tea and another top dress of charge. I'll take a picture tonight.
The problem started pretty much around the flip nearly 3 weeks back.
Does the lower pH of the run off indicate any problem?
Yes this is a good idea to give some natural food (compost tea ) and reset pH ... if it’s going in pH6.5 and coming out 6 then I’d water at between 6.6 to 7 next time.
The charge is aimed at microbe food rather than plant food but does contain a little..
Haven’t used the soil you’ve got so can’t comment on how strong or charged it is.. not sure if molasses is helpful at this stage... again this is a microbe food..
I would imagine your plant magic soil is designed to be used alongside the plant magic organic old timer nutrient range as not sure it’s a full ‘super soil’ which is one preloaded with dry amendments such as kelp meal, rock dust etc etc
Id be considering some liquid organic feed to supplement
old timer (plant magic) is very easy to use and cheaper than most btw
Can’t be sure tbh at this point though
Good shout. I will maybe adjust up my water to a higher pH within the range to see if that's frees up some nutes. I know the plant magic soil isn't particularly nutritious but was hoping the charge lived up to its name of being a complete fertiliser. perhaps next run I need.to add some things to the soil like dolo.ite lime etc.
I have some old timer nutes that came.with my kit so can supplement with them too. It just doesn't seem like a macronutrient problem. looks very much like Iron and potentially calcium and magnesium. I'll add a picture later. I definately also feel the lights are effecting too as I said the strips right under the lamp on both sides are less effected than either side. weird.
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