please please help, 3rd grow going down the drain

Hi All,

Someone please help me, I've grown in dwc before with no problems albeit many years ago.

My current grow is Matanuska tundra, these are about 4 weeks into veg and have started in the last day or so to die off (see pics)

I've hunted around the forums to find the problm but am completely stumped, I've checked everything I can think of (including flushing yesterday with plain RO water)

room temp is between 66 night and 72-74 day time (lights on)
humidity ranges from 55 to 75.
dwc water temp is constant 21 deg (there's no evidence of root rot, they are all nice and white, no slime etc.)

I'm using Ionic grow fert at 10ml per 10litres which gives me an ec reading of 0.45 with RO water, ph is kept at 5.8 (it creeps up slightly but has never been over 6.2, and after the first day usually stays stable).

Some are under a 600w hid lamp and some are under a 300w 7 band led lamp, although the same problem is starting to effect all of them.

The folowing pics are of the worst effected but even the ones that seemed ok yesterday now have on a couple of leaves starting to show the same problems beginning at the tips. It's unbelievable how the problem has progressed in only a matter of 2 days.

Years ago when I did this I never had any problems like this, I just used to set the nut. levels and ph and off they grew.

I'm really starting to pull my hair out this is the third grow I will lose if I can't solve the problem, the other grows failed due to the tap water I was using at least that's what I thought so I went out and bought an RO unit for this one. Everything was going superb until a couple of days ago when I noticed a couple of leaf tips on one plant starting to go brown/yellow.

please help!

are you supplementing cal/mag?

something I forgot to mention, it started with the smallest plants first, not sure if this is relevant but worth mentioning. I say smallest but they are all around 5-6 inches high and vary from 7 inches round to 12.

oh and I'm powering 8 buckets with 2 60l/min air pumps, each bucket has 2 2" round air stones.

i would say a p or zn deficency

Hi,
no cal/mag is not available here, I think you can only get it in the US

order some epsom salts from ebay its mgnesium sulphate add a t spoon to a glass of warm water to dissolve then add too res or watering programme. look for a good micro soloutin containing mg/ca/zn also good bacterium should help out no end

using r/o water, it removes everything, you need to replace the calcium,mag,iron and other needed things you removed.

shadowdarker said:

order some epsom salts from ebay its mgnesium sulphate add a t spoon to a glass of warm water to dissolve then add too res or watering programme. look for a good micro soloutin containing mg/ca/zn also good bacterium should help out no end

Click to expand...

I have epsom salts do you mean 1 t spoon per dwc bucket (1 bucket is 12 litres of solution), also any ideas on how long before I see an improvement?

It's wierd because the biggest plant doesn't seem to be effected that much, although like I say I've just in the last couple of hours noticed very slight browning on the tips on this one aswell.

If your right Shadow I'll love ya forever!!

VICTORYGARDENSHYDRO said:

using r/o water, it removes everything, you need to replace the calcium,mag,iron and other needed things you removed.

Click to expand...

But the nutrients I use have all that in them I thought?

When using r/o water you really should be using ca/mg with it... Theres nothin wrong with tap water as long as you PH it and It has a Low PPM...
If using tap water you wouldnt need to add the CalMag....
If it was me, i would just Flush with low ec nute solution for a few days, then start up with a different nute line if it kept giving me such problems..
Since your overseas, Canna is readily available and Excellent quality.... Canna Aqua Vega/Flores....

The r/o filter takes everything out of your water that would otherwise be available to your plants in terms of minerals/etc...
These have to be supplemented...

CalMag is most deff. available in Europe..

Orchid Accessories
61 Stanwell Lea, Middleton Cheney,
Banbury, Oxfordshire, OX17 2RF
England

That place might have it, they sell Dyna-Gro products... LoL... If in the one in a million chance ur anywhere near there...haha

spliffup1234 said:

But the nutrients I use have all that in them I thought?

Click to expand...

not the stuff you removed from the water.

jkahndb0 said:

When using r/o water you really should be using ca/mg with it... Theres nothin wrong with tap water as long as you PH it and It has a Low PPM...
If using tap water you wouldnt need to add the CalMag....
If it was me, i would just Flush with low ec nute solution for a few days, then start up with a different nute line if it kept giving me such problems..
Since your overseas, Canna is readily available and Excellent quality.... Canna Aqua Vega/Flores....

The r/o filter takes everything out of your water that would otherwise be available to your plants in terms of minerals/etc...
These have to be supplemented...

CalMag is most deff. available in Europe..

Click to expand...

My tap water comes out at over 0.4 ec, so you can see why I can't use it, it's also full of chlorine and some other chlor something hide chemical.

Where did you get cal/mag in europe, none of the local grow shops stock it. would love a link I'll buy it tomorrow.

I just ordered a batch of canna nutes from ebay, not related to this problem, just wanted to try something 'better' than ionic. I guess there's a reason they come as a 2 pack and not a single bottle of fert, I just used ionic because when I grew before I used it and didn't have problems, but hey different coutry and different tap water lol.

spliffup1234 said:

My tap water comes out at over 0.4 ec, so you can see why I can't use it, it's also full of chlorine and some other chlor something hide chemical.

Where did you get cal/mag in europe, none of the local grow shops stock it. would love a link I'll buy it tomorrow.

I just ordered a batch of canna nutes from ebay, not related to this problem, just wanted to try something 'better' than ionic. I guess there's a reason they come as a 2 pack and not a single bottle of fert, I just used ionic because when I grew before I used it and didn't have problems, but hey different coutry and different tap water lol.

Click to expand...

there is a lot of products for cal/mag
magi cal
calimagic
botanicare cal/mag plus
GH camg+
ect

spliffup1234 said:

My tap water comes out at over 0.4 ec, so you can see why I can't use it, it's also full of chlorine and some other chlor something hide chemical.

Where did you get cal/mag in europe, none of the local grow shops stock it. would love a link I'll buy it tomorrow.

I just ordered a batch of canna nutes from ebay, not related to this problem, just wanted to try something 'better' than ionic. I guess there's a reason they come as a 2 pack and not a single bottle of fert, I just used ionic because when I grew before I used it and didn't have problems, but hey different coutry and different tap water lol.

Click to expand...

http://www.plagron.nl/Index_uk.htm

This company sells Ca and Mg separately... They have several retailers in the UK....

Here's a pic of the bigger plant without too much of a problem, sorry about the pic but the lights have just come on.

Another unrelated question, do any of you think an ec of 0.5 is too low for this size plant? I seem to remember that I used to run my white rose at around 800ppm at this size, the ec in this bucket (changed out Monday) was at 0.51, it's dropped to 0.39 over the week, so I'm wondering if I should up the strength a little?

shadowdarker said:

order some epsom salts from ebay its mgnesium sulphate add a t spoon to a glass of warm water to dissolve then add too res or watering programme. look for a good micro soloutin containing mg/ca/zn also good bacterium should help out no end

Click to expand...

So I've just added the epsom salts, at 1 t spoon per bucket, will update tomorrow if there's any improvement.

k no difference today just getting worse, so I've backed off the nutes to 0.38 ec...will see in a couple of days

Todays pics, no diff, still getting worse, anyone got any ideas?

I've reset 1 tub with canna nutes at 5ml a+b 2ml rhiz and 2ml cannazym, all the rest I've backed off the ionic nutes by adding plain ro water, the tubs now range from 0.31 ec to 0.45, bit of an experiment to see which tub responds best. (ph's are all within 5.8-6 all stable)

Anybody think those nute levels are too low, given the size of the plants? I read other peoples posts and there all running nutes at .8 ec and up with plants a quarter the size.

VICTORYGARDENSHYDRO said:

not the stuff you removed from the water.

Click to expand...

I checked the ionic bottle it contains cal/mg/iron etc.

spliff, some of this advice sounds pretty bunk.

You don't need to go buy cal/mag or put epsom salt in there either.
When mixing your res you can add 10 or 20% tap water to the mix.
Your nute levels are low for that size plant. I run low ppm myself, but I go .7 to .8 EC for plants that size in veg.
If your girls are eating well, you'll want to frequently change the rez. When running low ppm your rez can run short of nutes pretty quick, so top off to .8 ec and 5.8ish daily.

quit using anything with the word zyme in it. Chlorine and chloramine are not that evil, I add both to my rez. (tap water and Zone)