Any advice from a seasoned DWC grower

I need some input about this grow. I have a multitude of experience in soil and Coco but this is my first attempt at DWC. The plants look healthy and are green, seem to be responding positively to the amount of nutrients I'm giving them. My question is does the slight yellowing of the lower leaves need to be a concern? They aren 3 weeks old from seed. PPM is a steady 600ish, water temp is from 68- 70 degrees and ECM is right at 1100. Any advice or tips will be appreciated.

Mr.Miagi77 said:

PPM is a steady 600ish

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i prefer ppm/EC to be dropping daily. along with water level. i'd lower it a bit.

What brand of nutrients are you using? How's your PH? A PH below 5 will make iron and manganese toxically available to the plant. A PH over 6 can lock out iron depending on how it's chelated.
I don't understand what ECM at 1100 means though.

I'm using General hydroponics Flora Nova grow and GH cal-mag the ECM would convert to 1.1. So you think I should lower the pH a little?

Oh and the PH as of 7pm was 5.88

I wouldn't worry much and I wouldn't change much. Your EC is just a touch higher than I run so I wouldn't worry much. I use .6 to 1 EC FNG in early veg.

That's kinda my thought as well, thanks everyone for the input and happy growing!

No need for "Calmag" in DWC with a already complete plant food. You could argue that it may be beneficial with RO water but I strongly disagree.

If you want to use Calmag to regulate and stabilize pH I would much rather use potassium silicate to accomplish this.

Thank you for the the wisdom, I'm learning every day and without you guys there ain't no me! Happy growing!

Here's a better pic of what I'm seeing today, the rest of the plant is very hethy looking.. thoughts?

Ph is fine at 5.8. The leaves could use some more green in them, in my opinion, so that's N.
Those burnt looking spots can be from low nitrogen; which I think they are.
They could also be light burn or maybe calcium deficiency, but I'm doubting that since you're adding it.
Not looking to argue with @rkymtnman but a PPM of 600 in GH isn't overly high.
They changed their feedchart format so it's hard to link it but the "medium" feed for week 3 is 650-850 PPM(1.3-1.6EC) and week 4 is 800-1000(1.6-2.0). Heavy feed is 850-1050 week 3 and 1050 to 1250 week 4. I know lots of folks on here run the lowest dose that keeps the plant healthy, but GH usually runs a bit higher PPM/EC than most other brands I've used. You certainly can't use that kind of PPM with Jack's or you'd fry them.
Me I'd go up to 800-1000 PPM and see how they do. I don't see much tip burn so you'll notice in a day if it's too hot for them.
Again, me personally, I wouldn't pull any leaves off a small plant, especially if there's a chance she's deficient.

MustGro said:

a PPM of 600 in GH isn't overly high

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i agree. that's why i said i'd prefer to see it dropping daily. that shows me it's eating: a steady ppm could also indicate nute lockout too.

Thank you for that info, I was debating adding more nutrients last night now I will for sure, so what do you think about 1/4-1/2 strength at first?

@Mr.Miagi77 I'm wondering what your water is for PPM? If you're starting with 200-300 PPM water it doesn't leave you much PPM for nutes in your 600 PPM mixes. How close to the GH recommended doses are you mixing. I mean how much of 3 part and cal/mag to a gallon of water.
Also how long you going between reservoir changes. Usually 7-10 days is recommended.
Those feedchart PPMs I listed above are for the whole GH line, so you'll be a bit below that since you're not running all the products. I should have thought of that before.

rkymtnman said:

i agree. that's why i said i'd prefer to see it dropping daily. that shows me it's eating: a steady ppm could also indicate nute lockout too.

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I see my PPM drop daily with big plants but his aren't so big and I find that small plants like to use a lot of water and a little PPM. Depends on how vigorous they are and reservoir size is huge in that also. I'm running a 40 gallon res with 18 plants that just went in 4 days ago. PPM hasn't dropped yet, not 1 PPM (Bluelab Guardian), but the res level is down a little bit. They're drinking fluids and I didn't get any wilting plants from TP shock, but they're too small to put a dent in the PPM in 40 gallons. Looks like a decent sized tote in the pic; maybe 5-10 gallons? Could be enough size to keep the PPM steady.
They're awful new to be nute locked, especially at 600PPM; but agree that a steady PPM could be nute lock.

Ok first I'll address"MustGrow". The municipal water here measures around 110ppm, not bad for city water, also I'm running the GH solution full strength. Now for an update since yesterday and it's a BIG difference! I raised my PPM to 820 and what a difference it made everybody. I just got home from work and they're praying to the light now and the difference in color is outstanding. Take in to consideration that this is my first attempt at any hydro system and so far Im very impressed with the growth rate, blows my mind compared to soil.
Last thing I have been changing my reservoir water every Sunday. Here's what they look like today compared to the other day. Thank you to everybody that took the time to help, I'm sure I'll need you again until I get this figured out.

Sorry I forgot to turn the red and blue off, if you wanna see them in just white light just let me know.

A soil grow will look pretty slow compared to hydro. I usually veg a month or less. Glad they're coming around; keep me in the loop.

you got some leaf margins curling up in both those pics. get that issue figured out and they look great!