My runoff PH is always too high

[bulletxs]

I'm growing autoflowers in soil and I cant manage to get my runoff ph to be under 7.0. Im around day 45 now from germ and its been this way for some time now. The water going in is 6.0-6.2ph and only once has it came out to 6.9. Typically the runoff is a little over 7. Is it a bad idea to run water ph'd to around 5.0 through it to attempt to lower the soil ph or is that asking for more problems?

 

[mckoomer]

I would say the runoff ph is a more accurate measure of actual soil ph . Must be something it the soil that is buffering. I would go 5.5 in see what comes out. Then adjust gradually

 

[Edinburgh]

Are your plants suffering? My tap water come out of faucet is ph 8.0 my runoff is 6.2 but unless my plants are suffering i rarely check ph, (all i grow is autos) you can buy water if its hard or off, you can buy stuff to raise and lower your ph, but with autoflowers you can tell if there running right, other things can throw off your ph such as types of nutrients over feeding ect, your autos are 45 days old they should be in flower and almost ready for bloom nutrients, i can give you better advice if i could see a pic of your plant, my ph bounces around a bit but what are your plants doing? Your sweating over something that may not matter in the long run yea we all want our ph perfect but sometimes its off i very rarely fix or even check ph unless im seeing a problem, i have run enough autoflowers to know there mo, lets see a pic this is my last grow of 2 critical autos i think i checked my ph 1 time but if i see something off the first thing u do is check ph and go from there, lets see a pic

 

[NairnM16]

If your in coco just keep watering till you flush out all the buffers nd wait till you get out what you put in or as close to it as you can, if it’s soil fk ns never felt with it

 

[JWM2]

What’s the ppm or ec of your input water? If it has few dissolved minerals then the ph reading is moot. It’s important to know what your water consists of before you make adjustments. If it’s 100-300ppm then the ph reading is probably pretty accurate. If your ppm is under 50 then the ph reading doesn’t matter as it will change as it moves through the growing medium and leeches the dissolved minerals. Low ppm water is great but you have to know how it interacts with your growing medium before you start making major adjustments.

 

[Jimster]

My philosophy is that if the plants are happy, leave it alone. Measuring runoff is a good way to get a general idea of root zone nutrients, chasing the Ph is often a recipe for disaster since it can initiate lockouts, deficiencies, and small Godzilla clones (only worrisome in Japan). I love my local tap water as it is providing minerals and a good Ph, but isn't excessive in PPMs.

 

[THCMonster]

Micronized sulfur or molasses are good PH downs. Both will naturally buffer the soil to a more acidic range, but like @Edinburgh stated before if your plants aren't suffering or showing signs of deficiencies then i wouldnt worry too much, 7 is neutral. Not the greatest PH range to be at but perfectly normal.

Watering with 5.5 water would just be a short term fix on the PH of the soil. As soon as the water evaporates it buffers out and you could do more harm then good. Plus you would be leeching out a lot of the PH buffers you have in your soil.

I would recommend adding about 30-60ml of molasses to the soil every feeding and that will do the job. Once the PH of the run off starts to get within range you can go back to feeding normally

 

[bulletxs]

What’s the ppm or ec of your input water? If it has few dissolved minerals then the ph reading is moot. It’s important to know what your water consists of before you make adjustments. If it’s 100-300ppm then the ph reading is probably pretty accurate. If your ppm is under 50 then the ph reading doesn’t matter as it will change as it moves through the growing medium and leeches the dissolved minerals. Low ppm water is great but you have to know how it interacts with your growing medium before you start making major adjustments.

Im on well water and the ppm is around 320.

 

[GNick55]

My philosophy is that if the plants are happy, leave it alone. Measuring runoff is a good way to get a general idea of root zone nutrients, chasing the Ph is often a recipe for disaster since it can initiate lockouts, deficiencies, and small Godzilla clones (only worrisome in Japan). I love my local tap water as it is providing minerals and a good Ph, but isn't excessive in PPMs.

Im on well water and the ppm is around 320.

soil has micro macro organisms that basically buffer the ph.

 

[GNick55]

soil has micro macro organisms that basically buffer the ph.

oh ya @Jimster has it right.

 

[bulletxs]

Are your plants suffering? My tap water come out of faucet is ph 8.0 my runoff is 6.2 but unless my plants are suffering i rarely check ph, (all i grow is autos) you can buy water if its hard or off, you can buy stuff to raise and lower your ph, but with autoflowers you can tell if there running right, other things can throw off your ph such as types of nutrients over feeding ect, your autos are 45 days old they should be in flower and almost ready for bloom nutrients, i can give you better advice if i could see a pic of your plant, my ph bounces around a bit but what are your plants doing? Your sweating over something that may not matter in the long run yea we all want our ph perfect but sometimes its off i very rarely fix or even check ph unless im seeing a problem, i have run enough autoflowers to know there mo, lets see a pic this is my last grow of 2 critical autos i think i checked my ph 1 time but if i see something off the first thing u do is check ph and go from there, lets see a pic

Here are 3 different auto strains all the same age. At one point they were all struggling badly with drooping, and lighter color leaves. Two of them in the photos are starting to get on the right track but I'm still struggling with one. All three have the same Ph runoff. My well water ph is in the high 7's so I use ph down from GH to get it closer to 6 when I water. Well waters initial ppm without anything added is 320. Ive added a small amount of nutrients early on from GH flora series but I believe that was too early and I had major drooping early on. The last few weeks its only been fed PHd water of around 6 without any nutes and theyve all gotten better than they were but still showing issues. Runoff is the same ph everytime of around 7.

The first image is a super skunk auto, My last watering was yesterday at a ph of 6.4, 320ppm no added nutes. Runoff ph was 7.1 705ppm.

2nd image is a Blueberry Cookies auto, watered 3 days ago at 6.2 ph, 320ppm no added nutes. Runoff on ph 6.9, 785ppm.

3rd image is a white widow x big bud. watered 3 days ago at 6.2 ph, 320ppm no added nutes. Runoff 6.95, 731ppm.

All images my camera flash is on.

I have general hydroponics flora trio series nutes plus a bottle of cali magic from them too. Ive stayed away from using them again from last times experience but maybe they're ready for some nutes? I've held off because I figured I needed to get my runoff ph in line first.

 

[bulletxs]

Does standing waters PH rise overtime? I watered one of the plants last night and the bucket that had the water was PH'd down to 6.4 and I had some leftover that I left out overnight. Just checked the ph of that same water before I dumped it today and the reading was 7.2?

 

[GNick55]

Does standing waters PH rise overtime? I watered one of the plants last night and the bucket that had the water was PH'd down to 6.4 and I had some leftover that I left out overnight. Just checked the ph of that same water before I dumped it today and the reading was 7.2?

yes it can do that, though depending on the chlorine level of your tap water, i usually let it sit at least 24 hours, i have a couple 5 gallon pails i keep rotating through.

 

[GNick55]

the droopy one needs nitrogen, they all do.
you might be over or under watering that plant or is it close to the light?

 

[bulletxs]

the droopy one needs nitrogen, they all do.
you might be over or under watering that plant or is it close to the light?

When I water I soak the entire pot until there is some runoff but not abunch. I water based on how heavy/light the pot is. I personally dont think Im over watering and more so think its a ph issue but this is my first grow after all so I could be wrong. Probably time for some nutes. Im running three led lights in a 4x4, two HLG 100's at 95 watts each and a blurple vivosun at 230watts. The lights are about 20 inches from the plants. Do I need to raise them?

 

[GNick55]

When I water I soak the entire pot until there is some runoff but not abunch. I water based on how heavy/light the pot is. I personally dont think Im over watering and more so think its a ph issue but this is my first grow after all so I could be wrong. Probably time for some nutes. Im running three led lights in a 4x4, two HLG 100's at 95 watts each and a blurple vivosun at 230watts. The lights are about 20 inches from the plants. Do I need to raise them?

i don’t know about those lights, someone should join in soon and let you know.
if your in soil try not to get run off as your micro and macro organisms will get washed out, you can a bit if you want your ph runoff.
can’t remember did you say your growing medium?

 

[bulletxs]

i don’t know about those lights, someone should join in soon and let you know.
if your in soil try not to get run off as your micro and macro organisms will get washed out, you can a bit if you want your ph runoff.
can’t remember did you say your growing medium?

Espoma organic potting soil

 

[bulletxs]

Micronized sulfur or molasses are good PH downs. Both will naturally buffer the soil to a more acidic range, but like @Edinburgh stated before if your plants aren't suffering or showing signs of deficiencies then i wouldnt worry too much, 7 is neutral. Not the greatest PH range to be at but perfectly normal.

Watering with 5.5 water would just be a short term fix on the PH of the soil. As soon as the water evaporates it buffers out and you could do more harm then good. Plus you would be leeching out a lot of the PH buffers you have in your soil.

I would recommend adding about 30-60ml of molasses to the soil every feeding and that will do the job. Once the PH of the run off starts to get within range you can go back to feeding normally

I see theres unsulphured and sulphured molasses to choose from. Which one do I want?

 

[GNick55]

Espoma organic potting soil

ok that soil came with nutrients, obviously it’s probably depleted by now so time to start feeding them, i’m not familiar with those nutes but usually half of what they say to use.

 

[Matthewstever]

I'd raise the lights a bit while they recover. I run my LEDs almost 4" up, 1200 watts covering a 5'x6'.space.