brown spots and necrosis. whats wrong? please help!

[mid-east-stone]

hey!
first , as one pic is one thousand words:















these are from my last grow.

strain: ultra haze #3
medium: soil (potting soil with some crushed tuf inside)
feed: not yet. they are just rooted clones.
ph: tap water is about 9 initialy, then it is about 8 after sitting for a while and then i stapilize it doun to 6 with vinigar. water run off is about 6.5 p.H.
watering regime: i use the "lift the pot" method which comes out about onse every 3-4 days.
lights: 250W hps.
temps: bout 28c day, 21 c night. (80-70 f)
i had this problem before and as i thought it might be some sort of fungus or a virus i have sterilised the pots, and soil with boiling water few times (the soil is new, not reused) and spraid my whole grow cabinet with iso alcohol till my dog was drunk.. : )
theese are photos of my previous grow, see the same symptoms:








what can this be?
a friend of mine is growing the same strain and has a huge success so i asume it is not strain related (We share clones so i guess i am right)
will be very thankfull of any input, aspecialy of those who had the same problem and got it fixed.
keep it running !
m.

 

[1G12]

Not really quite sure what's going on here. But, I would suggest adding a bit more perlite to your soil and making sure you keep it light and fluffy....don't pack it down in the pot. The roots like to be able to get some O2. Also, if you have newly rooted clones you might add some mild seed starter mix to your potting soil along with the perlite. This will make your soil less hot. Make a 50/50 mix of seed starter & potting soil.
Best of luck!!

 

[mid-east-stone]

thanks, Ig12.
do you think such a problem can be from too tight soil?
i think it is quite airy ....
m.

 

[sativa_cyborg13]

Still working on fixing my problem. At this point, I just dont want to see Kali Mist bite it. SSH ROM is still doing well. When I find out more, I will let you know because it seems that we have similar problems. Ordered that hygrozyme. Hope it takes care of my slimy roots. Hope you figure out your issue.

 

[Weedninja]

If your tap water pH is 9, you have VERY hard water. That means that there are high levels of calcium and/or magnesium dissolved in it. That can cause problems with other nutrients being absorbed. It can also affect the stability of your pH. Also, vinegar is not a really good pH down. 1g12 called it right about your soil. It looks like almost pure peat.

I don't know what's available in your country, so I would recommend that you ask your friend what he is using for soil and water.

 

[FreezerBoy]

vinegar is not a really good pH down

Vinegar is worthless at best. It will barely last just long enough to provide a misleading reading. In your case, it can become harmful due to your water's high alkalinity and the need for high volumes of vinegar. Get some pH Down.

 

[mid-east-stone]

weed ninja got it right and so did freezer boy

weed ninja got it right and so did freezer boy

the ppm of the water is bout 550 ppm.
will use destiled from now.
i thought that ph down is as good as vinigar.
i guess i was wrong...
i will keep you posted guys,
thanks!

 

[Sleepy]

i think your pH is too high and is not being adjusted correctly...

adjust your water to 5.8~6.5 range, then water...

do not use vinegar to adjust...if your water starts at 9+/- (like mine), do yourself a favor and get a decent pH meter also.

check the pH of any liquid you add to the plants' medium...adjust when necessary...

when your medium's pH is out of range, the plants can not absorb nutrients correctly. usually, we over adjust in a way that does not correct the problem, and we starve the plant to death and then kill it surprisingly quickly when the pH gets back into range...each stage is a mystery, because the correction you performed brings about another problem...(rambling, sorry...)

by the way, here is a concise definition of pH:

(from answers.com)
"pH:
A measure of the acidity or alkalinity of a solution, numerically equal to 7 for neutral solutions, increasing with increasing alkalinity and decreasing with increasing acidity. The pH scale commonly in use ranges from 0 to 14."


best of luck...

try to keep it in range.

 

[FreezerBoy]

the ppm of the water is bout 550 ppm.
will use destiled from now.

Distilled water is dead water. It's wet but, that's about it. Most nutes intentionally lack secondary nutrients expecting you to provide them through the use of tap water. Have some Cal/Mag handy.

 

[B.C.]

Has yer pete moss been limed properly?

 

[RC_Colas]

As the other posters have mentioned it looks like you have a nutrient block issue, but in addition you may be watering too much! Your soil looks very moist and based on the soil mark on the sides of the pot in has compacted due to heavy watering.

As for the PH (Hard Water) issue, can you find another source for water? I used the large 6 gallon water tank jugs and filled up in the city back in the day when my well water caused the same problem.

Good Luck.

RC_Colas

 

[mid-east-stone]

wow! thanks for the input!!!guys

wow! thanks for the input!!!guys

guys, you are awsome!
never expected so much help.
so:
1.what is the best ph down for soil? and as i think of hydro in the winter- is there one which is good for both?
2. i did not lime my soil. big no no ?
3. it is not to wet as i took the photo just after watering, i let it dry almost compleetly before i water.
4. so: tap water and distiled at 1:1 ratio will be better or worse then pure distiled with some epsom salt?
5. i will be at home only 3 weeks from now and a friend is taking care of them now so what are the simplest measures i can ask him to do so the problem will be solved?
guys, your are so helpull , thanks again ,
await your great input.
m.

 

[B.C.]

Rut Row!

Rut Row!

Yes sir, no lime is a -big- no-no. I'll bet it's been yer problem the whole time! Pete moss is low in PH, you need ta be adding 2 Tbls per gal or 1 cup of dolomite lime per cubic foot of soiless mix ta bring the PH up. I would suggest you go check out the sticky "Organics for Beginners" in the organics forum. Yul be glad ya did!.... ps. It might be a good idea ta use half distilled water and half tap water jus so ya don't over do it on cal and mag and also ta bring down the ph of the water itself. Good luck! BC

 

[Weedninja]

Yes, we are awesome.

Phosphoric acid is what 99% of the people on these boards use for pH down. I don't know what's available in your country, but I know that phosphoric acid is commonly used as a concrete and tile cleaner. I've never used industrial grade phosphoric acid for a grow, so I would be careful with it. I agree with BC about the 50%-50% tap and distilled water. Plants need calcium and neither epsom salt nor distilled water have any.

 

[mid-east-stone]

i am in the states so where do i get phosphoric acid from?

i am in the states so where do i get phosphoric acid from?

p.s.
i will be away from my plants for 3 weeks, as i mentioned.
do you think they will survive?
now- lime stone. just to crush it and add to the soil?
i will probably go on the 50:50 method as i get lots of almost d/w water from the a/c.
so - branded p.H. down or phosphoric acid?
in the mean while - some viniger or nothing at all?
i hope they will make it...
: )
and yep,
you are awsome!!!!
m.

 

[sativa_cyborg13]

Sorry bout suggesting hygrozyme. I was stoned and forgot that you were using soil, not dwc.

 

[Weedninja]

It's a tough call on whether they'll survive. You can buy powdered lime in bags in almost any store with a garden section.

Branded pH down is phosphoric acid, so if you can get it that way, its much better. Concentrated phosphoric acid is nasty shit.

If I had to choose between vinegar and nothing, I'd probably pick nothing. I've heard of people using lemon juice as a temporary pH down, but I don't know if it has staying power, or if it just fizzles like vinegar.