What am I doing wrong? Thought I`d got rid of this problem, but its coming back

[Tokesome]

Hi, I had a problem with my plants in the veg cycle. It proved to be a ph pen reading inaccurately and instead of giving them nute solution of mid 5`s as my meter was reading, they were actually having high 4`s and struggled badly and leaves showing intervienal yellowing throughout the plant. Here`s my original thread regarding this problem http://www.icmag.com/ic/showthread.php?p=2609736&posted=1#post2609736

After re calliberating my meter and got them back on track they shot off again bursting with vigerous growth. They got quite big compared with how I prefer to grow them, but I wanted them to recover fully before switching them to flower.

They`re now half way through week 3 of 9 flowering and I`ve just noticed a few leaves showing signs of intervienal yellowing again, they also look a little bit light in colour generally and not quite the rich green I`d expect.

My set up consists of 15 plants under 3 600 watt lights, in 3 60ltr nft trays and tanks. 5 pots per tank, each plant is in a 7ltr pot of coco and clay pebbles mixed 70/30, and a layer of clay pebbles at the bottom to avoid soggy roots, Each pot is fed with drppers (with the drip nodes removed allowing a free trickle of solution) and they`re set by a timer to come on for 3 x 45minute feeds during the 12 hour lights on period.

My nutes during the veg cycle was Canna Coco a & b, but I`ve changed to Bcuzz nutes as they were cheaper than Cana. Cheaper that is til I realised that you need to use it in conjunction with a Booster solution, and a bloom stimulator, the result being more expensive than the Cana and its recommended additive, PK13/14.

I`m sure my ph meter is reading accurately now, though I`ll check this again today against a ph colour chart kit I`ve bought. My meter is bang on in buffer 7 solution, whereas when I had my probems earlier in the grow it was reading at least .5 out.

There are not many leaves showing this problem but its showing on fresh growth since the problem was seemingly solved and is throughout the grow.

Other than that things look ok, plenty of bud sites and bushy plants. I`ll just go and knock the lights off and take a couple of pics so you can see the problem.

I really need to get on top of this problem as it affected my last grow where the yeild was just 19oz, whereas I`d expected around 60. My grow before that suffered also, but not as bad and the yeild was around 50 oz. I`ve thought along the line of whether the plants are a bit genetically poor, but my friend got a bumper crop from hers, and another friend has a couple which are only a couple of weeks from harvest and look to be doing well, despite an early setback of the same kind as my ph meter was being used there too. There has been no intervienal yellowing in either of these two grows, other than the second one I mentioned which was affected early on but recovered well and was the end of the problem.

Any ideas guys, help would be so appreciated.

I`ll be back soon with a couple of pics

I really cant afford for this grow to do badly as well, its been a depressing old time in that respect.

 

[Tokesome]

Ok I`ve checked my meter again and all is good there. I`ve also backed this up with a check with a liquid test and colour chart, I hate using them, but that checks out too, maybe giving a slightly higher ph reading, but only slightly.

I`ve just emptied and refilled my tanks, they`d all drifted down slightly in ph values except one tank that had drifted down a lot, like from 5.9 down to 5.3, the other 2 tanks had drifted down from 5.9 to 5.5 and 5.6. previous to this res change the ph had been remaining stable whether set to 6 or 5.6 or anywhere in between. Also the tanks were 3/4 used up and the EC reading had climbed from 17 to 23.

I`ve set them with a ph of 5.8 and EC14. Thats using the Bcuzz nutes and booster. It says on the instructions that for week 3 & 4 to add a dose of bloom stimulator too, but I haven`t bought any yet. I`ll try and get some tmro or Wednesday and add this to the tanks as well.

Here are a few pics of the grow and some close ups of leaves affected.

Thanks for looking guys any ideas or suggestions appreciated

 

[ibjamming]

Is this a joke? What are you doing wrong?

Nothing...you have girls to be proud of. Don't change a thing...

 

[Tokesome]

Its no joke, look a little more closely and see the results of the last 2 grows, they looked fine at times but the intervienal yellowing has just come back and its a sign that there is a problem and looking at what`s happened in the recent past I would expect it to worsen and affect bud production.

 

[dillhole]

First, a disclaimer: I know jack crap about hydro. That being said, I have grown in coco and they are similar. I have seen similar problems when the pH is too low and when there was a cal/mag deficiency.

Does your nutes have calcium, magnesium and other trace elements? And what's your water source?

DH

 

[EvilTwin]

Tokesome,
It could be as simple as the strain is prone to mg deficiency. Some are...I always add Epsom salts to my White Widow grows for example. So just add some mg and see what happens. 1/2 tsp MgSO4/gal would be a good starting point. Plants use the sulphur too and it's a cheap fix...
ET

 

[Lazyman]

Check the ph of your runoff, and adjust your input mix accordingly. I would also flush to make sure its not a lockout, then add slightly stronger nutes.

Looks like they want more N too, so I would add a bit of the veg nutes to your bloom nutes to balance it better. Do small steps, waiting 3-5 days between adjustments until you get it right. Too early for yellowing, so it's a lockout or not enough nutes.

 

[rocket high]

i had the same problem it was mag deficient . but the guys here helped a lot .added mag sorted now

 

[Tokesome]

ltr

ltr

Hey guys, thanks for your ideas.

I`ve checked thouroughly the ph situation, with my meter and drip test kit. Its set at 6.2 at the moment. With the Bcuzz a+b plus Bcuzz booster at EC14, it needs only 3ml of acid to reduce the ph to around 6.2 in a 60ltr res, so I dont imagine I`m using too much acid in the mix. I checked the ph of the run off from several plants today and found it to be exactly the same as is in the res, same EC too.

I filled the res` only yesterday and in one day the tank is about a quater depleted and the EC has risen from EC14 to EC17. I`m about to top up with fresh tap water and then deduce if the plants are taking up some of the nutrients. It very warm and humid though so evapouration may be part of the depletion.

They`re big girls now and only in 7ltr pots so I figure its pretty critical that I get this problem sorted.

Eviltwin and Rocket High, yes I agree it looks like MG def to me, dont know enough about it to decide whether there is too little N in the mix. I have some epsom salts, but I read somewhere, in the ask lucas thread I think, that Epsom salts were not good for the plants and that its better to use Calmag. . . . . I cant fint the relevant material now and cant remember why it was supposed to be harmful or inneffective. I know its a regular part of many grower`s mix though and I dont wanna leave them suffering at all so plan to add this tmro at 1/2 teaspoon per 5ltrs(aprox gallon).

I went to the Hydro shop today and came away feeling I`ve been duped into parting with cash. As I explained earlier I changed from Canna to Bcuzz nutes, the guy behind the counter said they work out cheaper. Then realised I had to pay another £15 on a litre of Bcuzz booster, and then realised I had to also purchase a litre of Bcuzz bloom stimulator, so I went to get some today. . . . . a whopping £27!!!

So how does that work out cheaper. the 5ltr a+b solution was I think about £8 cheaper than the Cana Coco a+b and with Canna it recommends there PK13/14 to be used for one week 3 weeks from harvest, 1 litre lasts a couple of grows (very upfront, no secret ingredients, you know what you`re putting into the feed) a litre of PK13/14 is about £15 and half is used in a grow making it another £7.50 to the extra £8 there a+b costs. Wheras Bcuzz requires the Booster, 1 litre will maybe last the grow £15, there its about even costs already, but then wait a minute another freakin £27 for Bloom stimulator makes it considerably more expensive.

I feel ripped off by the Nutrient manufacturers and again by the greedy shop pushing them, knowing that the customer is going to be back before long for another purchase.

Oops sorry, I`m ranting and dont want to water down (doh) the main reason I`m here, suffering girls!

I said this to the guy in the shop and he said with a smile on his face that people dont like paying for this one. I said it feels like a rip off to me, and asked him if he knew whats in it. He said "Its there secret ingredient, it makes it taste nicer".

I hate the capitalist ways of the business world, and I feel that I`ve definitely been screwed by them today

 

[Tokesome]

Hey sorry Dillhole, I dont know if there is sufficient mag and cal i the Bcuzz nutes, but after I`ve topped up my res`, I`m going to try and find out and google search for results.

Tmro I`m thinking of draining the res` and refilling with Ec14 and add the bloom stimulator and epsom salts.

One thing guys, when I`m aiming for my EC target do I incluide the epsom salts in the figure or add it on top??

 

[Tokesome]

Ok, I`ve filled the res` back up with tap water and the Ec reading is now the same again as it was after fresh res` fill up yesterday. Well one tank has dropped from 14 to 13, the other two res` are back to where they were. The ph is now around 6.4 to 6.5, I`ll adjust this tmro if I stick with the current nutrient solution.

This means my girls aren`t taking up their nutes as well as they should, and the yellowing is a little worse.

I`m unsure now as to whether I might be best to drain the res` and give em a fresh water flush for 24hrs, then give them a fresh nutrient res with the addition of Epsom salts. Or whether to get the epsom mixed into the current res` Mmmm what do you think guys??

 

[EvilTwin]

Hi Tokesome,
First I have to vent about people bad-mouthing epsom salts. Generally they're organic devotees who don't want any non-organic nutrients onboard. Cool... I Respect that.

But people who simplistically rejects anything that doesn't come in a bottle from the hydro store...well it's that attitude that I reject.

Epsom salts are ideal for Mg deficiency correction. CalMag adds the Calcium which may not always be needed.

Calmag has it's purposes. As a pre-soak for coco, it's perfect. As an addition to RO grows where nutrients (and water) don't always contain enough Ca or Mg.

You definitely don't want to use Calmag if you're using tap water (unless it's extremely low TDS).

I'm babbling (stoned) so basically, if you want to add Epsom salts...just do it. Won't hurt a thing. Every spring here in the mid-west, farmers spread the stuff by the ton to add Mg to depleted soil. I've used it for years growing White Widow and never had any ph shift or problems whatsoever...I think I'm finished. lol
ET

 

[Tokesome]

Hey ET, Thanks mate, I take your point there for sure.

Do you know if its cool to add it on top of the required nutrient EC or include it in the target figure. I`m guessing on top. but only guessing.

I`ll dose em up tmro unless I decide to flush em first.

 

[EvilTwin]

Hi guy...
Well everything that's in the res goes toward the TDS. So if you were right at the very max, then I wouldn't add anything else to it. But if you're at a level with room to play, then you're OK to add the magsulphate.

If you haven't used it before, it's a little odd. It sucks heat from the solution as it dissolves. So measure out what you're planning to add...then mix it up in a bucket with warm water. Once it's all dissolved...then add to the res.

You can usually find it in drug stores...to use when soaking a sprained ankle. Epsom salts is the common name but chemically it's hydrated magnesium sulphate.

Far as whether you should flush and start with a new res fill...I personally wouldn't. I'd carry on with what you have only with the addition of the epsom salts.
ET

 

[Tokesome]

Thanks for that ET. I`m gonna drain a 3rd or so off of each res then top up with water then add the Epsom salts as I think it`d push the EC/TDS a little high. I`ll also add the Bloom stim from Bcuzz. See how they do through the weekend.

Yes I`ve used Epsom salts before I still have a tub left, I`ll boil up some water and pre mix it. Assuming this is a MG deficiency, have you any idea how long it would be before I`d expect to see an improvement, and would I expect it to get a bit worse before it gets better?

 

[rocket high]

i seen a difference in the matter of three days tokesome , so dont fret my friend

 

[Tokesome]

Ok I set the res` at Res 1 Ec13, Res 2 Ec14, Res 3 Ec13, this included the Bloom stimulator. I added half teaspoon per 5ltrs of Epsom salts and its taken the Ec to R1 Ec16, R2 Ec 17, R3 Ec 16. A little high perhaps. I`ve added about 1-1.5 ml of ph down to bring them from 6.5 down to 6 in all the 3 res`.

See how they like that eh?

 

[EvilTwin]

T,
I'd think that you would see improvement in a few days. 3 or 4 maybe. And if it still gets worse...that just means it wasn't Mg deficiency. I've never seen Epsom salts do any damage so it's a no risk approach. Hope it works...
ET

 

[Tokesome]

Ah I missed your post Rocket High, thanks for the re-assurance. I gotta say that other than that they`re looking great, lots of strong branches and lots of buds, its almost filling my room. (That rerminds me of a thread on the overgrow site some years ago, it was called "filling my room" A guy in Oz where it was legal to grow one plant, he grew it to massive proportions and I think, if memory serves me correctly, he had 3 1k lights around it. I miss Overgrow, that was one hell of a forum.

 

[Tokesome]

Ah ET, I was posting at the same time. Well I`m hopeful at least. Everything else is set right and I`ve double checked everything everywhere. The yellowing has worsened as I`d have expected, but I`m hoping this will cease with the boost in Magnesium.

I`ll post developments guys