First grow, any idea what could cause this leaf damage?

hey all I am looking for some advice, this may not be the right place to post but I am a very green (lol) so try not to bash me verbally to harshly. So I noticed the following blotches on my leaves (pics hopefully included) and wanted to see if anyone knew what it was. The plants are about 3 weeks old from seed and I am growing indoors hydroponically (not even sure if people grow outdoors hydro) using general hydroponic trio nutrients. Pretty early on I had some temp issues but have since resolved them (the grow cab is now running between 72-82 Fahrenheit with a reservoir temp of 62-66 Fahrenheit). I thought this might be a magnesium deficiency but it seems a little early for that based on what I am reading. The pH of the soup is approximately 6.3 with blubbers going and around 6 without. I changed out the reservoir just today but thought that I would ask what ya'll think. The issue seems to have have the worst blotches on the the bottom leaves. I feared mites at first, saw a little webbing and about pooped my pants, but found a nice little spider hanging out and I have spent a least an hour and a half with a jewelers loop combing my plants and found no signs of animal life other than the spider. I may be over reacting, but I want to stay on top of any issues that may arise. Any help would be greatly appreciated.

CalMag can do that, and so can Phosphate and Potash, two of the three NPK's. Anytime I get that, I just scale back on my feeding to zero for a while, since most nutes are premixed in some ratio anyway, i don't spend too much effort figuring out which specific one, ya know?

Try a ph range of 5.5 -6.2

Kinda looks like mold or blight...u got gnats?

Thanks for the posts y'all. I will try taking the pH a little lower for a few days and if that doesn't work run them on pH tap for a little while. I do not think that I have gnats, but I am fairly new so I could be missing them. Because it is basically my first run through I am just trying to trouble shoot things as they arise. Mold or blight sounds kind of bad, would that start on the lower leaves and work it's way up? Also I have six plants growing but only two are showing these symptoms. Should I remove them from my grow?

my plants are doing the same thing right i doing my first grow as well in a super soil so i only using water but it got me tripping are your leaves cracking at all?

I have noticed a little cracking in a few leaves and surprisingly the stem on one seems twisted. New growth all looks fine :/. It has presented a wonderful/stressful little puzzle to solve.

I go with punk. Mine did that only worse. Spots ended up holes. No nutes new growth is fine. Was trying kick start em

that actually looks like Cal deficiency, check this out http://www.growweedeasy.com/calcium-deficiency-cannabis , looks like your pic to me, but Cal deficiency usually starts on newer growth, so may be wrong, since you said it was lower leaves. i'm not very experienced with hydro, but everything i've been reading has said 5.5 to 5.8 is "perfect" range for hydro.

@Tallapoosa, yikes holes in the leaves would have me all sorts of stressed out but thanks for the feedback. @Roger, thanks for the link and for the advice. I think you and CannaOG are definitely right that the pH is a little too high. Thankfully that is a pretty easy problem to resolve, few drops of pH down and should be good to go on that remedy.

Is it humid do u water alot??? Try foilage feeding cal-mag if problems not resoved your problems are far worse

Yeah I'm pretty sure I caused it sprinkling water soluble nutes expecting rain and only got a little. Apparently concentrated and was also having tiny grasshopper problem. They seem to be fine now. Lesson learned. ..

Throw some habenro and cayenne peppers around ur stuff

dabbindylan said:

Throw some habenro and cayenne peppers around ur stuff

Click to expand...

Thx, I'll try it.this is guerilla grow, can't get out there but twice a wk. . Prob enough dew to wash spray off