One month to go, yellow leaves with brown spots

[smpaz420]

i have a few plants, some of which are developing some yellow leaves and brown dead spots on them. they are growing in FFOF, using FF nutes, i worked my way up to full strength and they burned a little bit. i watered with only water 3 times after that, tap water ph is around 7.2 or a little higher, all i have now is a drop ph indicator. the runoff was at a ph of 6 ( or lower test only goes to 6 ). i gave them 1/2 strength nutes after these pics were taken. any input is appriciated!

smpaz420 Reviewed by smpaz420 on 09-24-2008. One month to go, yellow leaves with brown spots i have a few plants, some of which are developing some yellow leaves and brown dead spots on them. they are growing in FFOF, using FF nutes, i worked my way up to full strength and they burned a little bit. i watered with only water 3 times after that, tap water ph is around 7.2 or a little higher, all i have now is a drop ph indicator. the runoff was at a ph of 6 ( or lower test only goes to 6 ). i gave them 1/2 strength nutes after these pics were taken. any input is appriciated! Rating: 5

[phatsesh101]

yellowing in flower is normal idont see any nute burn it usually starts at the leaf tips and ur tips dont look burnt how much air is beeing pushed through\


fill out the problem work sheet

[stinkyattic]

How long have they been in those pots? Your soil chemistry just went screwy, evidenced by leaf issues and low runoff pH. I'm guessing they've been in those pots well over a month...?
Water VERY HEAVILY at 7.5 until the runoff comes up to almost 7, and then water again with 1/2 strength bloom food at pH 6.7 to finish the flush.
We see here the major drawback of SCROG... difficulty in accessing the pots nad re-potting if the need should arise.

[smpaz420]

thanks stinky, i thought i would try scrog but its to much work and i think i will end up with less than last time. yes they have been in these pots since i started flower, i have done everything the same as last time except the scrog. it has been hot here as well and i cant afford to keep the air as low as i need to keep them properly cooled. it has been in the mid to high 80s in there, but i have it on at night to kinda offset the heat.

Can you recommend a good ph meter? something under 100 bucks would be great. thanks stinky and phat.

[stinkyattic]

For $7 you can get a bottle oh liquid pH indicator drops, which is all a soil dude really needs for the rare times you have to mess around with your pH.

If it's super hot, spend the $$ on a good exhaust fan to add even more ventilation. Your plants will be okay up to about 85'F if they have lots and lots of fresh air.

You can get a GREAT effect with less work with a simple Sea of Green setup, but the trade-off is higher plant count. It's very popular though, and really easy to do especially if you have a mother plant who gives you clones every 2 months.

[smpaz420]

i was looking at a hanna ph and temp meter at my lhs, but the drops sound alot more affordable right now. I am running a vortex 6" fan right now and i have a circulation fan inside the closet, so i am changing the air 5 times a minute i would say. i would love to duct some ac in there, but i didnt want to cause any smell issues, not like its a big deal but i do want it to be as inconspicuous as possible. thanks for your input.

[stinkyattic]

Good call on the big fan and the a/c. Check that your intake hole is LOW and LARGE- at LEAST 6" diameter, preferably a pair of holes, to make maximum usage of the blower you have.

Also avoid Hanna products like the defect-ridden plague they are, that can only read accurately when the solution has the ionic strength of fucking WASTE BRINE and even then aren't trustworthy! I wouldn't use one of those to test the water in my crapper, let alone my grow!

[smpaz420]

LOL thanks that would have been an expensive mistake. yeah i was just thinking i could duct through to the next closet in my "office" so the light intake is separate from the room and get another vortex just for venting the room. What i have now is a gap under the door 2" high and 24" long so its pleanty of area for the fan, and i also have 4 3" abs vents in the platform i put in there. having been in there with the door shut there is alot of air moving. but i think separating the light and room exhaust is the best idea, i already have a speed control for the vortex so i could use that to control temps when it starts getting cold. thanks again stinky, you really know your stuff and i thank you for all your help so far.

[stinkyattic]

If you split the light exhaust and room exhaust, you then have the option of ducting a/c in there and even running CO2. And that could be

[smpaz420]

which ph test would you recommend? i went an bought a cheapo one and its not exactly what i thought it would be. it works though just want something that i will be able to test my water with more accuratly.