yellow leaves/brown spots

[Sexypenguin41]

hey everyone. i'm around 5 weeks into it and my plants have had minimal problems until now. my plants are in fox farm ocean forest mixed with perlite, humidity around 45% temperatures range from around 69-77 degrees, the PH of my runoff is between 6.0 and 6.4 i've got 8 daylight 23 watt cfls ranging from 2-4 inches above the plants and one 43 watt bright white bulb lowered down on the side to get some light underneath. I use ferts every other watering (which with these plants is about every 35-48 hours... they drink a lot lol). The lower leaves starting turning yellow and had a few brown spots. I think this might be a magnesium deficiency so i put two pinches of epsom salt in the water two days ago when watering. Is that what this is? and if so, will the chlorophyl come back to the leaves that are yellow?

[Sexypenguin41]

ok, i checked the ph again, and it's possible that the ph is below 6. the testing solution i have only has a scale from 6.0-7.6 If that's the case, how would i raise the ph?

[Sexypenguin41]

seriously... it's getting worse. BUMP!

[VegasMade1]

hey man i just had this problem, you burning you plant fast. Stop adding nutes ASAP. Let you soil dry completly out and then flush it using just Ph adj water(not sure on how to raise the ph, heard pinch of baking soda works. Go to pet store and get ph testers, letting you soil dry very well before next watering. Plant should recover bout a week later man. Check my thread and see if my pics look around same.I transplanted asap, and she started to perk up withing a day or 2. Its looking mag def. most likley because too many nutes. in your soil can block other elements out that your plants need. Also salt-build up can occur. Dont take my advice to max, im still pretty new and learning. This is just from my knowledge and wut ive read.

[MTheory]

Originally Posted by Sexypenguin41

hey everyone. i'm around 5 weeks into it and my plants have had minimal problems until now. my plants are in fox farm ocean forest mixed with perlite, humidity around 45% temperatures range from around 69-77 degrees, the PH of my runoff is between 6.0 and 6.4 i've got 8 daylight 23 watt cfls ranging from 2-4 inches above the plants and one 43 watt bright white bulb lowered down on the side to get some light underneath. I use ferts every other watering (which with these plants is about every 35-48 hours... they drink a lot lol). The lower leaves starting turning yellow and had a few brown spots. I think this might be a magnesium deficiency so i put two pinches of epsom salt in the water two days ago when watering. Is that what this is? and if so, will the chlorophyl come back to the leaves that are yellow?

That looks like either a pH problem or nutrient lockout. Before you do anything, buy a electronic pH meter! Here's a good cheap one: http://www.eseasongear.com/phtehahiwh.html
Stop giving nutrients and flush the soil. Buy some distilled water and adjust it to a pH of 7. Bring your plants into your bath tub. Pour twice as much water as the volume of your pots through your soil. For example, if you have them in one gallon pots, use two gallons of water per pot. At first, pour a little at a time and wait a few minutes, then pour more. Make sure the soil is evenly moist and it starts to drain. Then fill the pots to the brim, wait til the water goes down a little and fill it again. Kee doing this until you've poured all the rest of the water through the soil. Check the pH of the runoff toward the end and it should be between 6.2 and 6.8. Also, watering every 36 to 48 hours seems like a lot. You should make sure the top inch of the soil is dry before watering.

[Sexypenguin41]

oh i do. i wait till the pot becomes very light and the leaves actually start to droop. these suckers just go through water that quickly. but i have started flushing and i have ph testing solution which works well enough