Beginner grower help with light setting

The plants are 16 days old from the day I started germ. I have the mars hydro SP 3000. What setting should I have plants on? I have my lights placed 24 inches above the plants at 75% right now. Should I increase the light intensity? Should I decrease? Should I raise the lights to about 30 inches?

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What do the plants tell you? Are the leaves changing in anyway as in tacoing, are they stretching a lot as in growing tall and skinny?

If they are cupping I’d say back it off some, if they are stretching a lot then lower the light a few inches, then see what happens again…



Seems just fine to me. I wouldn’t mess with it just yet, maybe others here have other opinions??

okay so don’t raise the temp? When should I?

Each model light has its differences not sure on your model but this chart and link to video explaining specs etc and hanging height recommendations etc.
Looks like a great light


Well…first a disclaimer, I’m still new to growing cannabis myself, but I have been growing veggies and peppers for years and years…and if I learned anything, it’s let the plants tell u what they want to do by being observant.

I am running a mars hydro ts1000, which only draws 150w to your 300w. I was at 24”(ish) at 75 and noticed one of my plants growing tall very fast…so I lowered the height down to18…then I noticed 2 plants started to have crinkled looking leaves…so I raised it. I am currently sitting happy at about 22”, and I’m on day 18. Still only at 75-%…I will bump mine just slightly starting at day 21 about 5-% a day till I get to 100% because I’m starting to see them spread out some.

To get to my decision, I downloaded a free iPhone lux app to measure my light, then looked up where I should be and at what stage. I’m starting at day 21, as that’s what I’m actually going to count as my “veg” day 1 where as the first 21 I’m counting as a seedling.

Here is a pic as of about 3 hours ago, you’ll notice a silver haze in the middle, I started her way late and she will go outdoors at day 21):

Here is power recommendation based on stage of growth all hung at 19.5” I believe

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See so one of my plants are doing really well while another one of my plants are suffering. It’s getting little brown dots all around the leaves. Is this a nutrient deficiency? I transplanted them into fox farms ocean forest median and didn’t add nutes since it’s a hot soil. I put worm castings in yesterday but it’s too soon to tell if it worked. Do you think this is a light problem or nutes? Is there anything else I’m missing? I’ll add pics but I’m unsure how good you can see.

I see it, I’m not to sure…like I said I’m new to cannabis, but in the world of veggies that would tell me that it has too much fertilizer…so I’ll tag a few others for you that might know, @Hellraiser @Myfriendis410 @Covertgrower maybe if if these guys know and can help

Last picture the leaf probably got wet while watering, that one will probably die off. It happens.


Yea I didn’t put any nutes in it until yesterday because I figured it was doing that because of a deficiency. So I added a little worm castings. But when I transplanted, it went to a hot soil so I never added anything.

The bottom leaves I wouldn’t worry about too much probably just got wet, if seeing brown spots elsewhere, it’s usually a calcium deficiency, common with the use of RO or distilled water and treatable with Calmag.

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What’s RO?

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Reverse Osmosis water - another form of purified water, just not as pure as distilled water.

Okay well I water with faucet water

May not be the problem then unless you have really clean tap water. Another cause can be too much light intensity in veg, the more light you throw at them, the more nutrients they require and can cause deficiencies as well. Maybe back off the light a bit, you really don’t need more than 50% of your light’s capacity while in veg.

so is this what you meant by leaves cupping? Does this mean the lights are too high/close or is this normal?

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Looks good to me.

Looks good to me too.