First Time DWC Grow/Light Brown Spots Help??

[dr3n]

hey everyone, first time grower, first time grow, first time everything really.. please be gentle..

 

started my seed off a week ago.. I'm using a DWC oxypot with three part advanced nutrients at 1ml per ltr for the first week..

 

My little girl seems to be doing ok - she's growing quickly but as you can see from the pic there are these little spots on her leaves.. Are they anything to worry about? Do i need to do anything to fix her or is this normal??

 

Any help or advice would be really appreciated if possible please folks..

Edited August 7, 2021 by dr3n
spelling errror

[Shumroom]

Welcome to UK420 @d3rhn 

 

I could be wrong.... 

 

 

It looks to me like it's been splashed with water/feed then burned by the light. 

 

I'm no DWC expert, 

but I'd maybe fill the basket with more pebbles, 

to stop any splashes coming from below. 

 

If you don't already, 

I'd recommend you start a grow diary. 

 

It's a great way to learn and it helps us to help you

 

Atb 

 

 

[stu914]

Hi and welcome,

 

I'd say that's a deficiency...bit more info on your set-up please...nutrient temps and which 3 part advanced are you using?

Which strain is it, how long has it been in pebbles and what are the roots looking like?

 

[dr3nai]

Thanks both..  so wasn't aware about nute temps? I've been adding and mixing them in (along with the rest of the water) at "straight out of the tap" temperature..

 

I have just checked that though and in the oxypot its all currently sitting at 72f...

 

The advanced nutrients i am using is this micro/grow/bloom three part mix..

 

 

 

In terms of the strain its a chronic lights, but as she's only 5 days old - i don't want to pull the peat pellet out of the pebbles to check the roots just yet - feel like is too early and i might damage it??

 

In terms of a diary i am definitely keeping one and keeping a log of everything i am doing.. On Monday it will be 7 days, so plan to change the water and move up from 1ml per ltr (of micro/grow/bloom) to 2ml per ltr as per my funny little spreadsheet:

 

 

 

Does this all sound right or am i doing things wrong?? thanks again for your help - totally noob when it comes to all this..

Edited August 19, 2021 by Owderb
Pic removed. Please upload to here. Thanks

[badbillybob]

what does the ec  come out to with 1 ml per litre?

what is the ph ?

 

you need to top up the hydroton, to stop light getting into the res as this will cause algae, which will kill them.

i wouldnt worry so much about the brown spot yet...

[stu914]

@dr3nai

 

Your plant is currently putting down roots so there won't be much top growth just yet.

 

Don't pull the roots out of the pebbles, that will cause more problems than it solves but as Billy says, the pebbles need to be up to the top of the pot.

Lift the pot and and see if there are any roots showing underneath. How far is the base of the pot above the nute solution?

Res temps at 72f is ok...optimum temps are 18c to 22c and can be difficult to keep in range both summer and winter.

 

Those nutes are 'ph perfect' and need no adjustment (they don't work properly if you do) but you need to know the strength.

I use their base a+b grow and bloom and it's very strong so I would be wary of increasing dosage going by some chart or other,

better off reading the plant and see what it needs, start at 1ml per ltr and work up as the plant grows.

 

Have you a CF/EC meter or truncheon?...you'll need one, this will tell you if the plant needs stronger or weaker nute solution,

Bluelab truncheon is pricey but it's the best.

 

 

 

 

[dr3nai]

i've just got a ec/ph meter - will go check and report back.. thanks again everyone..

[dr3nai]

So my EC/PH Meter turned up.. Then i had to get some distilled water.. however, the results are in - PH is 5.9 - EC is 1033 - ECu is 939 and PPM is 537..

 

On the whole (i think) she is looking ok.. She still has her two initial derpy leaves.. But the rest of the new ones seem to be ok with no spots or anything.. I have quite a lot of roots coming through the basket now which i am also taking as a good sign?

 

Here's what she looks like now - week 2 will be Monday.. i stuck to 1ml per ltr on the advanced nutrients for her first water change.. But thinking of pushing that up to 2ml per ltr on the next one ( which will be Mon)...

 

Does this sound/look right to everyone else??

 

Edited August 19, 2021 by Dodgee
Remove off-site pic

[Rural Buddha]

I'm far from an expert @dr3nai but I would go easy on the nutrients still. I think I've seen elsewhere on uk420 that EC in DWC systems might be ideal at around 1200 once the plant is well established. A search for 'dwc growing ideal ec' brings up a load of hits, this from one of them - An indicative EC range for cannabis plants is 0.8-1.3 for seedlings; 0.5-1.3 for clones; 1.3-1.7 under vegetative phase; 1.2-2 during flowering. Different varieties of cannabis might require significantly different values of EC.

 

Your plant is looking OK at week 2 though the tips on some leaves look odd, difficult to tell under the blurple light. Don't kill it by overfeeding, the charts the nutrient sellers show shouldn't be wrong, they will have done their research on strengths in perfect conditions done by experts. I've barely used half the recommended doses (CANNA nutrients in coco coir) and done OK and produced live plants and good crop.

[Haze_smoker]

Go easy on the nutes mate! I had my last run in a single bub like u at 0.8ec for about 3 weeks.. she didn't like it above 1.0 so I left it at that the hole way thru. It was about 5 n half 6ft tall by week 6 and still on 1.0ec then I started to drop back down... dwc is different from any other growing method. 

[stu914]

On 12/08/2021 at 10:17 PM, dr3nai said:

thinking of pushing that up to 2ml per ltr on the next one ( which will be Mon)...

 

Difficult to see for sure but the leaf tips look a bit burnt so I would hold off increasing nute strength for now.

You'll find that it needs to stay low throughout the grow because the roots are constantly submerged and it's very easy to overfeed.

[dr3nai]

Thanks again everyone - you guys are seriously stopping me from tearing my hair out with this.. Just a quick update.. Went to my local hydro shop and they also suggested that I add a bit of Calmag and spray her with some techboost xl twice a week.. This seems to have fixed the brown spot issue.. Or its at least keeping it at bay for now.. I have reduced the water in my pot by 1ltr to make a bit of an air gap - will be week 3 on Monday and she now seems to be looking a lot better:

 

 

Edited August 19, 2021 by Owderb
Pic removed. Please upload to here. Thanks

[Shumroom]

Hi there @dr3nai

 

Once that spray runs out get some 'cold pressed seaweed extract'. 

 

You use 2ml per litre of water so a 500ml bottle of seaweed extract will make 1000 litres of excellent foliar spray. 

 

 

Also I noticed that your photos are hosted offsite, 

this is against site rules. 

 

You should upload your photos to here into your own gallery of images. 

 

 

 

 

Atb 

 

 

[dr3nai]

hi - thanks, will look for some cold pressed seaweed extract and give that a go.. have re hosted my pics on here but seem to have lost the edit button for my posts.. if/when it comes back will fix the hosting issue - thanks again for your help folks..

[Shumroom]

Unfortunately we can only edit our posts for a short time after we've posted. 

 

Perhaps a moderator can assist, 

@Dodgee with the editing of the previous posts/photos? 

 

Looking forward to seeing how you get on with these

 

Atb