Goldberg is incorrect, always add the lime for 2 reasons: 1) lime has a lot of calcium in it which marijuana uses a lot of and 2) fertilizer is a salt, which is acidic and will lower the pH in the medium over time so better to do it just in case. Just make sure it's either dolomitic or agricultural lime, which are the same thing. Plus it's very cheap to boot. Like he said, loads of bad info on here.
Promix + high alkalinity water
- Thread starter canadiankushman
- Start date
GOLDBERG71
Well-Known Member
I bought a soil meter and tested it throughout the whole life of my plants. My mix stays at 6.5 from start to finish with no D lime. (I only tested during flower because it was the 4th week of flower where my issue was showing up) Yes lime does have calcium in it but my plants aren't lacking calcium. So adding more isn't helping me. Maybe you're using more peat moss than I am?? I cut my 3.8 pro mix with 4 cf of perlite. I don't know what else to tell you other than its working fine for me and my testing of the soil and results of product of just dandy. By all means if it makes your results better do it. I just don't need to.
Last edited:
SamsonsRiddle
Well-Known Member
I never said anything about adding lime, as i never had a need to nor was ever suggested to when i was learning about promix.The only suggestions I got was to add perlite and vermiculite. It comes out to a very nice even texture when you do this, but neither is going to stabilize your ph.
As far as not ph'ing anything, that's what i read from homebrewer. that's what i have done. never had a ph problem. apparently neither has he since he stopped and he has also seen no negative results.
Some things are just assumed by people who have never tried thing themselves. Then they are repeated and repeated over and over again.
Once again I see some guy on here suggesting cal-mag, for example. If you have a complete nutrient with all the macros and micros in the right ratios then you won't need calmag, even with RO water. (Goldberg should know this since he uses dynagro).
Back to the op - if you have ro, why waste time with 8.1 tap? Why mix it? Why don't you just get a simple one part like dyna-gro which will provide everything you need in one bottle with stripped water? I still think you need to let us know your watering frequency and volume for a better assessment of your situation, because those stems look like they are floppy as fuck.
thumper60
Well-Known Member
pro-mix is not soil why do u keep calling it soil?it is soiless treat it like hydro ph should be 5'8not6.5! 6.5ph is for soil grows.u talk a good game.but it's BS
bravedave
Well-Known Member
Another bit of BS you were handed was the denouncement of 20-20-20 ferts. Its just fine for veg. If you are fertilizing every third grow with low dose, I would fertilize every water. Lastly, someone also said to go find some marijuana specific nutes. No need. Having a colorful cartoon on the package doesn't help grow plants.
Alexander Supertramp
Well-Known Member
Looks like N toxicity. Back of the food a bit.
Alexander Supertramp
Well-Known Member
Just sitting here shaking my head.....
Alexander Supertramp
Well-Known Member
It is soil. Just a different type of soil than you will find in your yard. The whole soiless thing is just stoner logic.pro-mix is not soil why do u keep calling it soil?it is soiless treat it like hydro ph should be 5'8not6.5! 6.5ph is for soil grows.u talk a good game.but it's BS
boilingoil
Well-Known Member
Use nitric acid for pH down with high alkalinity water. I grew for years with water that was 380 ppm with 285ppm of that being CaCO3.
thumper60
Well-Known Member
so u saying it's fine to run to run water at 6.5,while running pro=mix.?
Alexander Supertramp
Well-Known Member
Yes it is. No matter what pH the water going in is. It will still buffer to the mediums pH in less than an hour. Like others have mentioned it is a good idea to amend Promix with 1-2 tablespoons of dolomite lime prior to the grow. It does contain some lime right from the bag. But not quite enough in most cases to complete the grow. Also adding some EWC to the mix will help greatly. Add the dolomite and EWC and never worry about pH again.
thumper60
Well-Known Member
ewc added mean's u running soil not soiless .I never have had ph proplems in pro=mix is hydro READ peace dude
boilingoil
Well-Known Member
Lime is added to peat products as a buffer as it has a relative pH around 4.9.
SamsonsRiddle
Well-Known Member
dude, you don't have to add anything to not have to ph your nutrients going into promix. if all of you don't believe it, like i didn't at first, then just try it and find out for yourselves. In fact, try to ph your nutrients to 6.5 then do it to 5.8 then just stop ph'ing your nutes like i said before because you'll have the same results. I didn't figure this out on my own (like i said, i also didn't believe it at first), but am here telling you i have tried it and it is true.
Alexander Supertramp
Well-Known Member
I know Samson that there is no need to pH solutions when growing in peat based mediums, havent pHed ever. I use promix among other peat based mediums. And understand how plants and mediums work. And the only place Thumper you will find folks treating peat based mixes as hydro is cannabis forums. I think it makes them feel more in control of things.
Edit: Correct you do not have to amend with dolomite/EWC. But it sure helps a newb grower who has a tendency to over feed. The additional buffer will help tremendously.
Edit: Correct you do not have to amend with dolomite/EWC. But it sure helps a newb grower who has a tendency to over feed. The additional buffer will help tremendously.
Last edited:
canadiankushman
Well-Known Member
Ths
My logic was that i was liming with every watering due to the high alkalinity water. Ive switched to 50:50 tap RO which puts my ppms at 120 before nutes.
I was adding an insane amount of phosphoric acid to try rid my water of the bicarbonates which were causing my ph to rise. I wasnt sure if it was too much additional Phosphorus that was causing my medium ph to climb or the bicarbs but i believe it to be both.
Also, my humidity is stupid low but my temps are a good 76F. My humidity is less thsn 20%. Ive resorted to misting them with RO 3-4 times a day to get the leaves drinking and its helped so much. Plants are perked back up and my new adjustable RH humidifier is on its way.
Im not a newb by any means. Im just new to using straight PROMIX HP.
Ive grown indoor, outdoor, soil, coco, perlite hempy's.
Ive had much success but i admit thst this issue had me scratching my head.
My leaves look great now. They have their suppleness back and are standing up nicely.
Thanks for all your help folks!!
Thanks.
My logic was that i was liming with every watering due to the high alkalinity water. Ive switched to 50:50 tap RO which puts my ppms at 120 before nutes.
I was adding an insane amount of phosphoric acid to try rid my water of the bicarbonates which were causing my ph to rise. I wasnt sure if it was too much additional Phosphorus that was causing my medium ph to climb or the bicarbs but i believe it to be both.
Also, my humidity is stupid low but my temps are a good 76F. My humidity is less thsn 20%. Ive resorted to misting them with RO 3-4 times a day to get the leaves drinking and its helped so much. Plants are perked back up and my new adjustable RH humidifier is on its way.
Im not a newb by any means. Im just new to using straight PROMIX HP.
Ive grown indoor, outdoor, soil, coco, perlite hempy's.
Ive had much success but i admit thst this issue had me scratching my head.
My leaves look great now. They have their suppleness back and are standing up nicely.
Thanks for all your help folks!!
canadiankushman
Well-Known Member
And ya, by the pics the stems do look floppy. These are all sativa (haze) hybrids that will grow tall if allowed. They have long but woody stems like willows.
They seem to take our outdoor prairie winds just fine so im not worried one bit about them indoor.
She's all good now boys
They seem to take our outdoor prairie winds just fine so im not worried one bit about them indoor.
She's all good now boys
Hawzzy
Member
You can soak a bath towel in water...hang it up in the space over a tray or bowl to catch drops to raise the the RH. Little desktop mister/humidifiers at wallyville for 15 bucks maybe.
Pls let us know how you continue and your results of ph adjusting your water...or not...I for one am interested. My first grow was in Promix and I started running into problems with multiple symptoms....UNTIL I started to check and adjust the P.H of my water and nutes....the ph of the soil and runoff were insanely low....and my tap water starts at 7.5.
I have a rdwc grow and Promix grow...quite small...but im interested in how you continue and your results kind sir.
Pls let us know how you continue and your results of ph adjusting your water...or not...I for one am interested. My first grow was in Promix and I started running into problems with multiple symptoms....UNTIL I started to check and adjust the P.H of my water and nutes....the ph of the soil and runoff were insanely low....and my tap water starts at 7.5.
I have a rdwc grow and Promix grow...quite small...but im interested in how you continue and your results kind sir.
canadiankushman
Well-Known Member
My first post must not have posted.. strange..
Anyway, i just said that ive been misting with ro water often and did a flush with RO then watered with 50:50 tap:RO (120ppm) and 1/2 strength jake's 3 part.
I think the issue i had was possibly a combination of nitrogen tox from letting them dry out just a bit too much, too high ph, from either my crazy high bicarb tap water, or phosphorus tox (from the insane amount of ph down i was using). All this coupled with ultra low humidity(less than 20%!).
New adjustable RH humidifier on its way, lots of recent misting is getting the leaves their suppleness back as now they are able to drink and nitro claw letting up.
Getting back on track.
Going to let them dry about 2/3 then give light multi/day waterings.
Im hoping to get this room on a gravity fed drip system soon. These plants will be flowered as soon as their clones take root.
Thsnks all!!
Anyway, i just said that ive been misting with ro water often and did a flush with RO then watered with 50:50 tap:RO (120ppm) and 1/2 strength jake's 3 part.
I think the issue i had was possibly a combination of nitrogen tox from letting them dry out just a bit too much, too high ph, from either my crazy high bicarb tap water, or phosphorus tox (from the insane amount of ph down i was using). All this coupled with ultra low humidity(less than 20%!).
New adjustable RH humidifier on its way, lots of recent misting is getting the leaves their suppleness back as now they are able to drink and nitro claw letting up.
Getting back on track.
Going to let them dry about 2/3 then give light multi/day waterings.
Im hoping to get this room on a gravity fed drip system soon. These plants will be flowered as soon as their clones take root.
Thsnks all!!
canadiankushman
Well-Known Member
I grt the feeling that promix nute ph is such a hot issue because everone is right. No one knows the quality of water the next guh uses and ph ing the water removes the bicarbonates. You need some bcarbonates so you dont run out of bffering half way through a grow so i think in my case 50:50 RO:TAP will work best for me because i wont have to ph my water adding more P to my ntes.
Unless of course i went to sulfuric acid or nitric acid to nuke the bicarbs.
TBH, I am interested in seeing what sulfuric acid woud do for my buds...