Yellow/brown spots on leaves

• Lamptype (HPS/MH/CFL): HPS
• Wattage: 600W
• Lamp distance to plant: 110 cm
• Light cycle: 18/6

• Temperatur in room: 25-28 celcius in shade. 29-32 celcius directly under light
• Humidity : 40-60 % during light and under the plant. 11-30 % in the middle on room
• Ventilasion: http://www.clasohlso...fte/Pr364150000 and 2 chassi fans that runs during light period. I also have an intake/ outtake that runs 24/7

• Soil: Canna terra professional 11 L / pot
• Nutrients: Canna terra vega

• Age of plant: about 40 days
• Height: about 20 cm
• Strain(s): Big Bud och Pure Power Plant
• From clone or seed: Seed

• Watering rutine: In the beginning it was about every 5 day with CFL 250w. Now with the HPS 600w I water every 2nd or 3rd day.
• How much water: About 1 liter / pot
• How many waterings with neutrients: 1 each 3 times

Things I did during the time the spots started to show:

Changed from CFL 250w to HPS 600w, they are still at veg stage (18/6).

Accidentally poured about a total of 0.3 liters of ICE cold water with a ph level of 8.5 + on the plants. (To lazy to pour the humidity bowl water in the sink so I poured it on the plants).

Accidentally poured about a total 0.3 liters of normal tap water with a ph level of 8.5 + on the plants. (To lazy to pour the humidity bowl water in the sink so I poured it on the plants).

Waterd them regularly with a ph level of 6.0-6.5. ( Today i try to give them a little higher (6.5-7.0).



Pic:

Sorry for HPS pictures. I did not have brighter light to take the picture. The brightness of my rooms lamp is very dark and my camera very bad.

hi im no expert but with the ph issues you might have a lock out of nutes, do you ph test your run off?? you can also get a fungi that can do something similar, id be looking more towards a deficiency of sorts though, maybe flush with clean 6.5 test run off then see where you are?

depending on your PH level you may have to raise or lower it. if its 6.0 or below then molybdenum, calcium, phosphorus, and magnesium gets locked out. also check to see if the dirt is too wet or too pact down that could put a stress on the roots nutrient uptake of boron, iron, manganese and copper and zinc those elements are also only absorbed at a 6.0-6.8 respectively.

Can't enlarge the pics because it's full of spam! Wish I could help but I can't see the pics.