Help!! White spots in centre of leaf purple stems, browning fan leaves

Hi my set up is as follows help and advice appreciated thanks !

What is your experience level? Novice 2nd grow 1st was not what I expected

Your Equipment:
.1) Type and wattage of lights. 600watthps
.2) Distance from tops? 2,5ft
.3) Reflector type? Air cooled
.4) Is there a consistent fresh air supply? Through the reflector
.5) Do you have an exhaust fan and a circulation fan? One oscillating fan and 5inch cfm extractor fan




Your medium:
.7) Specific brand and type of soil, canna terra profesional
. Size of container. 20l air pruning pots
.


Your nutrients and water:
10) Source of water? ph7.8 tapwater ec of 0.6
11) Method of checking water ph. ph pen
12) Method of adjusting water ph. (ph down
13) Specific brand and N-P-K ratio for each bottle. Bio bizz grow npk8 2 6
14) How often are you watering between feedings, and how much per watering? Water once a week or when pot is light , feed every 3 rd water, adding 1ml per 5litres of superthrive adding 0.1 ec of cal mag , using 0.8 ec of feed including 0.6 tap water ec


17) What is your ingoing water's ph? ...your runoff ph? 6.5 going in normally between 5.8 and 6.2 coming out

1 Do you foliar feed? Canna cure once a week just before lights off
Your growroom:
19) Indoors or outdoors? Indoors
20) What size of closet, room or hut? Dr120 tent
21) What are the temps and humidity levels while lights are on? 24-28 ...With lights off 18-22. Humidity between 35 and 50% lights on 45 55 lights off

22) Have you seen signs of insects in the growroom? No sighns of pests
Your strain:
23) What strain are you growing? White rhino green house seeds
24) From seeds or clones seed
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I've been having trouble with this plant to say the least I thought it may have been a calcium def despite using tap water supplemented with cal mag , symptoms have persisted to get worse i removed some of the large fan leaves to start with as I thought it may have been spidermite damage even tho theres been no sigh of pests and weekly sprays with cannacure , my other plant is doing great which is green house seeds trainwreck, but the white rhino Is stunted and been a slow grower from the beginning.. Pics follow please comment looking for an idea as I can't pin it i thought nute burn , underfeeding . Anyone ?

Anyone ?? Will add more pics of progressing symptoms

are you misting the plants when the lights are on with water? is that photos with natural light? If not can you take one with natural light im getting an "orange" hue and its throwing off

There are a few things that can cause the spots.... It could be the foliar spray burning the plants... do it an hour or so before the lights come on (use a green light to work in- doesn't effect the plants!) You want the leaves to dry before the lights come on.. you DON'T want nutrients or other liquids sitting on the leaves during the dark- can cause Gold-spot fungus... which you MAY already have-- but don't think so...

The purple stems are often normal for MANY strains-But the leaves do seem somewhat pale...

Your Ph is low-- should stay above 6.5 GOING IN even after adding nutes to the water... Comming out isn't as important if your soil is buffered...

Feed 1x a week and use a mixing schedule... feed DEEP- 1/2-1 liter of solution per gallon of soil in the planter...
then water between feeds ONLY if the top 2 inches of soil get dry & the planter feels light...

Add some Earth Juice Micro-blast OR Super Cal Mag to your nutes, get your ppm's and Ph in-range for that age of plant... I'll post the feeding chart for Bio-Bizz below....
Follow it according to the age of your plant....
and get some good Ph adjuster - make sure it is between 6.5-7.0 GOING IN after mixing!
[FONT=&quot]GHBB (Bio-Bizz) OMRI Schedule[/FONT][FONT=&quot]

PRODUCTS NEEDED:
Bio- Grow= $16
Bio- Bloom=$16
Top Max Stimulator=$20
Alg-A-Mic (for hydro only) $18

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[FONT=&quot]WEEKLY FEEDING:[/FONT][FONT=&quot]

Week 1: 1 tsp Grow
Week 2: 1 tsp Grow
Week 3: 1 tsp Grow + 1 tsp Bloom + 1 tsp Top-Max
Week 4: 1 tsp Grow + 2 tsp Bloom + 1 tsp Top-Max
Week 5: 1 tsp Grow + 2 tsp Bloom + 1 tsp Top-Max
Week 1 of 12/12 : 1 tsp Grow + 3 tsp Bloom + 1 tsp Top-Max
Week 2: 1 tsp Grow + 3 tsp Bloom + 1 tsp Top-Max
Week 3; 1 tsp Grow + 3 tsp Bloom + 1 tsp Top-Max
Week 4: 1 tsp Grow + 4 tsp Bloom + 3 tsp Top-Max
Week 5: 1 tsp Grow + 4 tsp Bloom + 4 tsp Top-Max
Week 6: 1 tsp Grow + 4 tsp Bloom + 3 tsp Top-Max
(For Sativas or plants that need 7 weeks or more to bloom, continue with week 6 until flush)
Flush with Carbs if you wish, or plain water for last 2 weeks.

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I have done when the humiditys been low. ah sorry hps is on I will take pictures in natural light in the morning and post
thanks for your response

Thanks for all the info I think the foliar spraying with the canna cure just before lights go Off is what could be causing the problem I noticed tonite that some of the spots seem to be turning into brown patches on the fan leaves coming from the middle, could this be the gold spot fungus ? I will start feeding once a week with the bio grow and bloom, As for adding super cal mag ive been using a ml per gallon of a similar product with cal mg and a small amount of N will I need to add more despite the water being hard ? Thanks

Anyone help on this one