Yellowing, brown spots, and holes, with pics.

Thanks for taking a look. Had some PH problems early on but bought a new meter. I like to keep the PH 6.2 and let it fall to 5.6 or 5.7. Tried using Lucas Formula but my plant started getting brown spots in random areas and a hole developed in some of those areas. The big fan leaves are yellowing between the viens and lots of yellowing on the top growth. Need help before it gets worse please. Only nutes I have added ar GH Gro, Bloom, and Micro. Very little of the Gro is in the res right now. I added one part Micro with 2 parts Bloom. The more Bloom added, the more brown spots and yellowing I got. CalMag is the only other nute, 1tsp per about 10 gallons. Using 600 watt HPS. The yellowing is getting worse, please help.

Are the PPM to low? Should I use Lucas and bring the PPM to 800 or more? Tap water is <100ppm and current ppm of the system is ~600. Went in to flowering 3 weeks ago. I am concerned about using the Bloom. As I said in my first post, the yellowing, brown spots, and holes appear worse when I add the GH Bloom.

Please help!

The yellow and brown spots stoped after I stoped adding GH Gro. They yellowing at the tops of the plant has gotten worse. I am wondering if it is heat dmg, light burn, or a nute deficiency. I've moved the light up as far as I can and recently put a better fan in facing the top of the lights and top of the plants. Here are some updated pics. Any help would be appreciated. Thanks.

looks like there may be some heat stress but what is the humidity in the room and are youfoiler feeding them at all?

ChaosSelling said:

looks like there may be some heat stress but what is the humidity in the room and are youfoiler feeding them at all?

Click to expand...

Humidity is about 45%, though when I look at the min/max temps max shows temp 85F and humidity 99%. Low temp of 65F. I don't foilier feed becuase I smoke the leaves and don't know if it's ok to smoke leaves spraid with chems.

I am using LST and supercroping to get more distance between the top of the plant and the light. I have done this several times throught the grow and it does seem to help the yellowing a little.

With the plant growing towards the light every day, I need a way to slow down the growth. I am going to try and change the light on/off time so that the light is on during the day and off at night. Currently the light is on at night (security reasons) and the dark period is during the day. My cab is not completely light proof and I am wondering if the dark period in the day is causing more growth and less bud formations due to light leaks. I have been 12/12 since 24 Nov. Will changing the light cycle now hurt the plant? Does this plant look on track to harvest in a month?

Thanks for the help!

Acid

Opened the cab this morning a few hours after lights out and found the humidity was at 99%! The air in the cab was very thick. I will now keep an exaust fan on 24/7 to keep the humidity lower.

holy crap dude.. 99% ?? yeah get some air flow.. its also good for bugs.. they don't land and nest on the leaves