ok starting a few 5 gal buckets with promix ultimate organic with 25% perlite…will this be ok to use like this…and when should I add nutes? Can I go ahead and add armor si silica or will that be bad? I have GH trio, Calmag, Armor SI, hydroguard…how and when should I use what I have?
The way I understand it, pro-mix is soilless, so you’ll wanna start adding nutrients at 1/4 strength after about two weeks. I believe @Hogmaster or @Countryboyjvd1971 uses promix, maybe they can help
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ProMix is peat which is light weight, drains well, but has little nutritional value. I usually assume peat is acidic (low pH). Coco fiber is similar, but not acidic. Read @garrigan62 soil mix recommendations. Another reference is Buildasoil.com.
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You will also want to ph to 5.5-6.2 for pro mix with 5.8 being your target ph.
I’m using the sunshine mix and had to start nutes after about the 3rd watering. Again very light mix at the start. Peace. 
So can I use it comes from the bag without issues…mixed with 25% perlite? Have General Hydroponics Trio (Micro, Gro, Bloom) Calmag, and Armor SI silica, and hydroguard…thats what I have for dwc but soil idk. Not wantign to buy a bunch of stuff but Promix ultimate organic can I grow like it is without problems?
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Let me tag @MattyBear. He uses pro mix and is very familiar with what’s what. I’m learning every day too. 
. I’m using mine as is.
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ok cool…also…Im trying soil because my dwc keep getting root rot from hot temps this year…can I keep it 80f if in soil?
I disagree… Promix should be treated like Coco or even soil. Hydro PH of 5.8 does npt work as well even though the company may recommend this. I buy ProMix by the bale and it is good enough for 4 weeks of vegging before you have to add nutrients. After about a month start using 3 part at 800 ppm. Once you induce flower mix solution up to a range of 1000-1200 ppm. If you feel the need to add nutrients earlier make a solution in the range of 400-600 ppm. You should never need CalMag unless you use the “Lucas” formula in flower (0-1-2). There is plenty of Calcium in 3 part and Promix has Dolomitic Lime which is a form of Calcium and buffers the PH so if you get the PH close the Dolomitic Lime will buffer it to a safe range.
Hope this helps. I think I have an old paper I wrote on 3 part in the GrowFAQS.
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You would prefer the soil to be a little cooler. So placing a white piece of plastic as a cover (plastic mulch) will help keep the root zone cooler. A small piece of Panda plastic would work great.
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Thank you for the clarification @latewood. So it’s buffered to ? 5.8-6.0 ?
What should the PH of my water be (distilled)…so for first 3-4 weeks no nutes just PH’s distilled water…what PH…and can I add armor SI before the 3 weeks (silica) or is that a nute that will add to much in beginning?
Promix is used for your base to mix your own soil
That depends on what kind of Promix is being used. Some are like what @latewood said and come precharged with nutes but I use Promix HP and that is inert with no nutrients added. Just peat mix and perlite added in for drainage. They aren’t all the same and that can make it difficult when diagnosing sometimes 
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This is what I got what your thoughts? Promix
That Promix comes charged with nutrients and is Organic. You don’t need to add nutes for a few weeks and I’d try to ph between 5.8-6.2
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I don’t feed for at least the first 3-5 weeks from seed I use azos and mykos when I start them after 3-4 weeks I transplant then 5-6 week I feed and I ph like soil like 6-6.5 never failed me and they get big and I use promix bx and use nothing but promix and my nutrients
what about armor SI (silca) can I use that or is that considered a nute?
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You don’t need silica if using soil. Only media like coco and Promix (peat) and of course; hydro.
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I did not say it would buffer to 5.8-8.0; I said dolomitic lime acts as
a buffer to keep PH is a safe range. I use 6.1-6.5 for PH of Promix
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