Is this Something I should Worry About?

I keep finding these spots popping up on my leaves. I thought these were Nutrient drops, but they are showing up too frequently.

Beginning stages of phosphorus deficiency is what it looks like to me. I’d be concerned about it yes as it will only escalate in flower. I’m not overly familiar with DWC. What’s your pH and EC as I’m sure inquiring minds will wanna know.

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Yes, I am using cal mag. the DWC holds about 1.5 gals and I put somewhere between 3-5 ml of cal mag in on my last fill (I forget exactly how much ti was last time). my I keep the pH around 5.9. Not sure what the EC is but I can measure it and let you know.

Someone else mentioned Calcium deficiency because my pH is below optimum level for calcium absorption.

@TheAlchemist what can I do about phosphorus deficiency?

If your pH is 5.9 that’s in a good range so again having an idea of what your EC is may help. Double check your pH tho. What week are you in, nutes etc? You likely just need to bump up your P and back down your N slightly. I’ve found that cal mg deficiency looks like yellow striping in between veins and not bronze splotches at early onset so cal mg isn’t my vote but I’m also not an expert esp in DWC. It’s also very hard to over feed P so again, pH and EC.

This is my first attempt at growing, so forgive me if information seems irrelevant. At this point, I’m not sure what info is helpful all the time.

I measured the EC and it’s at 625

To give you context, I am in heading into week 5. I planted the seed on June 20 and moved it to my DWC on June 29 (I should have moved it earlier). I was late to start nutrients. I am using GH Nutrients Flora Gro, Flora Micro and Flora Bloom along with Cal Mag, Revive, and Hydroguard. I had been adding Recharge to it as well, but I’m going to stop using it for now.

My DWC holds 1.5 gals. The method I have been following is to start with the full recommended dose of GH Gro and Micro. Add Micro to the water first to make sure no nutrients are locked out. Start with 1.25 ml/gal week one and increase 1.25 ml/gal each week until you reach an absolute max of 15 ml/gal. When I transition to flower, I will switch out the Grow for the Bloom and back down nutrients 1.25 ml/gal each week until 2 week before harvest when I stop them completely.

Cal Mag I have been following the dose on the bottle. I think it recommends 3-5ml and I opt for 5.

As far as the Revive is concerned, I think I added 3 ml. I was advised to use 3-5 ml each fill of Revive.

The Hydroguard I have been following the dose on the bottle.

pH from what I understand I have been doing slightly wrong. I have been testing my ph and adjusting every day to keep it around 5.8. From what others have been saying, it should be allowed to rise to around 7 because that is the prime pH for calcium absorption.

2 also did have a 10 oscillating fan blowing somewhat directly on the plant. I moved that out and moved in a clip fan which is much smaller and the breeze is not as intense. I had heard too much air can cause burns. I have 2 600 watt blurple lights that were about 24 inches above the plant, which I was told might be too close so I moved them about 6 inches higher. I have been trying to keep the humidity around 50-75 % and the temps around 80-85. I’m trying to keep the humidity from creating condensation to avoid droplet burns or heat stress while also keeping the temps down.

She’s a Blue Dream Fem, for reference.

I can dig it. @Myfriendis410 may have some insight.


Need to see plant in natural (white) light: overall picture and one top along with any issues. No blurple please!

This will burn your plants. You have to mix to a target TDS: I’m assuming “EC of 625” you actually mean 625 ppm on the 500 scale.

This is what you are supposed to do: do NOT let it run up to 7.0. Everything is readily available in your solution at 5.8 PH.

This is going to cause you all kinds of problems. You have to have a meaningful amount of liquid to avoid massive swings in TDS and PH.

What is your water temp? If it’s over 70F you are flirting with trouble too.

Nutrients are mixed in a specific order for the same reason they are packaged separately: they have to be diluted before blending and in a specific sequence. Micro is first. If you run silica that would go ahead of anything else. If dosing cal mag it goes in after silica and before Micro.


I have a water chiller. It’s set to 65 F. What size reservoir would you recommend?

The 625 was in cm. the TDS is 287 PPM Currently.

So, when I’m adding the nutrients, what is the target PPM?

Also, I want to make sure I have enough Air roots exposed out of the water.

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my plant looks about like that mid week 4 and im blasting them with 900PPM of nutes.
I did get a bit of nitrogen toxicity (curled tips) though so I wouldn’t go that high.
But by the looks of the spots it seems you have a deficiency, I would feed more.
Maybe around 700PPM?
let me tag someone very knowledgeable with hydro for you


you want your water level about 2 inches below the net pot.
im not sure if im seeing correctly in the picture but it seems your water level is at the bottom of the net pot.

There’s about an inch gap.

To make sure I’m understanding this correctly, basically when I’m done adding the nutrients, revive, hydroguard, and cal mag, I should have a reading of close to 700 PPM?

Additionally, I just bought a similar DWC system but with a much bigger water capacity to replace this (gonna re-purpose this one for other veggies). As soon as it arrives and I add the solution, I’ll move the net basket. Same size net baskets, so hopefully it won’t be too traumatic.

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Yes i would raise PPMs to at least 500.
But im also on my first grow so im not extremely knowledgeable.
I did tag someone that is super knowledgeable with hydro for you though.
But yeah, def raise the amount of nutes, i was feeding 250PPM at the seedling stage.

I should note that my water from the RO is 25 PPM.

You want 1 1/2 to 2" of air space between bottom of net pot and liquid. Air stone should deliver what looks like a rolling boil in plant rez.

That’s kinda up to you and your space. The easiest might be something like a 28 gallon yellow-topped tote. I use 18 gallon for my plant rez and it allows the plant to grow into 12 gallons or so of liquid.

I would be ramping up and at around 500 to 600 ppm of base nutes for another week then push to 750 give or take for the rest of veg. Once you flip your ratios will change somewhat but peak TDS no higher than 900 to 1,000.

Of course; look at your plant for it to tell you if it’s happy. Your plant pretty much is so your environmental conditions are good.

Look up ‘VPD chart’ too which can help you with maintaining proper Vapor Pressure Deficit.

FYI anything under 100 ppm is unreliable for both PH and TDS due to low conductive path.


What he said…:point_up:


@Myfriendis410 @peachfuzz haha glad to know my advice was not far off :sweat_smile:


can you explain what you mean by flipping my ratios? is that when i stop grow and start bloom?

Yes: the grow schedule will explain

when i did my drain and fill today, the tds reading after adding the two base nutrients was around 600. added a good dose of Revive too and the correct dose of cal mag

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