DirtyStrawHat
Active Member
i had dumped solution in through the medium, and also test samples of the water i had used to test ph, never raw nutes, i was trying to not have to open the top as much as i could
PH dropping quickly, cant get away from 4.6
- Thread starter DirtyStrawHat
- Start date
DirtyStrawHat
Active Member
also rot may be the case here but ive had rot before never did it pull my ph down that hard
rkymtnman
Well-Known Member
it looks more like staining to me.
if a much bigger res isn't possible, is there a drain in that gatorade cooler or a spigot? if so, buy a standalone res outside the room. drain your gatorade every day at lights on, and refill with fresh nutes daily. your pH problemm will go away.
Wastei
Well-Known Member
I keep journal of all my grows and back in 2011 I had a lot of issues starting out growing in DWC. I've noted drastically drop in pH. I tried a lot of thing starting out in water culture and when the pythium problems was fully established I had to start over.
Noted brown sludge coating exactly everything except some roots in solution. Black patches and roots disintegrating between fingertips leaving just the inner core/string left. But the smell is the best giveaway, rotten carrots is exactly how it smells like to me.
DirtyStrawHat
Active Member
yeah it dosent smell, thats why i was thinking it was staining aswell but it cant hurt to add bennies and water level for the time being not sure what rez im going to use next this 8g is not cutting it either not even going to bother im thinking of going with a trash can at this point keep the same shape less and make a small access window
Yes to a point it will increase initially. Then as the leaf is damaged and the plant is trying to conserve moisture it will slow and even stop transpiration. I can copy paste a VPD thread I made on another forum it's quite long but I feel does a good job explaining how transpiration is affect by environmental factors.
OK here is a copy paste from a post i made elsewhere. Its info i have taken from a few sources and added to in order to help get all the info in one place and add some info i felt was missing.
WHAT IS VPD:
VPD stands for Vapor Pressure Deficit. All gases have vapor pressures, but when we’re growing, we’re interested in water vapor. Vapor pressure deficit is the difference between the pressure of water vapor in 100% saturated air at a given temperature (basically a leaf’s vapor pressure) and the air’s actual vapor pressure. A high VPD value raises a plant’s transpiration rate and increases nutrient movement through the the plant’s xylem, while a low VPD value slows the movement of nutrients through the plant.
WHY SHOULD WE CARE:
VPD control is related to the following:
You reach expert growing level when you learn to manage humidity and VPD. Everybody spends their time managing temperature, nutrients, and whatever else, but the last little thing you learn to manage is humidity, and it is significantly more finicky.
HOW TO STEER PLANT GROWTH:
In order to stay on the same page, I should point out that relative humidity (RH) andVPD are inversely related. This means that when relative humidity (RH) is high, VPD is low, and vice versa.
When growers want to know how to steer plant growth, they are interested in maximizing growth. So let’s start with how the plants react to changes in VPD:
Effective VPD control is about balancing gas exchange. There is a “Goldilocks” zone where the plant is getting everything.
If your VPD is too low, then your plants aren’t going to acquire enough nutrients, slowing growth; if your VPD is too high, you’re going to stress the plant and the stomata will close, rendering your extra carbon dioxide ineffective. Like everything else with growing, there’s a Goldilocks zone. One VPD is too high, one VPD is too low, and one VPD is just right. There are charts of a VPD curve with a three way graph of humidity, temperature, and growth. There’s a sweet spot along the center of the chart.
DO NOT USE THIS CHART ITS REFERENCE ONLY
A VPD chart for a hypothetical plant, image courtesy of Argus Controls. The far left side of the graph is too wet for the plant,
and nutrient uptake is inhibited. The right of the graph is too dry for the plant and stomata close, inhibiting CO2 uptake.
WHAT IS VPD:
VPD stands for Vapor Pressure Deficit. All gases have vapor pressures, but when we’re growing, we’re interested in water vapor. Vapor pressure deficit is the difference between the pressure of water vapor in 100% saturated air at a given temperature (basically a leaf’s vapor pressure) and the air’s actual vapor pressure. A high VPD value raises a plant’s transpiration rate and increases nutrient movement through the the plant’s xylem, while a low VPD value slows the movement of nutrients through the plant.
WHY SHOULD WE CARE:
VPD control is related to the following:
- Increasing or decreasing metabolic rate
- Improvement in yield quality
- Determining plant stresses
- Pathogenesis (more on this later)
- Carbon dioxide injection (more on this later)
You reach expert growing level when you learn to manage humidity and VPD. Everybody spends their time managing temperature, nutrients, and whatever else, but the last little thing you learn to manage is humidity, and it is significantly more finicky.
HOW TO STEER PLANT GROWTH:
In order to stay on the same page, I should point out that relative humidity (RH) andVPD are inversely related. This means that when relative humidity (RH) is high, VPD is low, and vice versa.
When growers want to know how to steer plant growth, they are interested in maximizing growth. So let’s start with how the plants react to changes in VPD:
- The bulk flow of water changes within a plant’s xylem as VPDchanges.
- If you have a high VPD, meaning that the RH is low, the plant will increase its transpiration rate and start pulling water faster from the substratein an effort to stay cool and moist.
- If the VPD is too high, the plant will become stressed, leading to inefficiencies.
- In the same vein, if the VPD is too low, meaning that the RH is high, the transpiration rate will decrease, slowing the flow of water through the plant.
- If you have a high VPD, meaning that the RH is low, the plant will increase its transpiration rate and start pulling water faster from the substratein an effort to stay cool and moist.
- Nutrients follow the flow of water through the xylem and into its various tissues. Nutrientslike calcium primarily move with the bulk flow of water through the arteries of the plant.
- If you’re injecting carbon dioxide, you want the plants’ stomata to stay dilated for as long as possible. Ideally, the stomata would be fully dilated at all times to maximize carbon dioxide use. Plants open and close their stomatato regulate moisture loss.
- If you have a high VPD, or low RH, your plants are going to close their stomata to reduce water loss. When the stomata close, you’re not getting adequate gas exchange, and you’re not making the most of your carbon dioxide.
- If you have a low VPD, or high RH, plants will open their stomata and let in more carbon dioxide.
Effective VPD control is about balancing gas exchange. There is a “Goldilocks” zone where the plant is getting everything.
If your VPD is too low, then your plants aren’t going to acquire enough nutrients, slowing growth; if your VPD is too high, you’re going to stress the plant and the stomata will close, rendering your extra carbon dioxide ineffective. Like everything else with growing, there’s a Goldilocks zone. One VPD is too high, one VPD is too low, and one VPD is just right. There are charts of a VPD curve with a three way graph of humidity, temperature, and growth. There’s a sweet spot along the center of the chart.
DO NOT USE THIS CHART ITS REFERENCE ONLY
A VPD chart for a hypothetical plant, image courtesy of Argus Controls. The far left side of the graph is too wet for the plant,
and nutrient uptake is inhibited. The right of the graph is too dry for the plant and stomata close, inhibiting CO2 uptake.
VPD IN DIFFERNT STAGES OF GROWTH:
Ideal KPA ranges for different stages of growth.
As a matter of fact, most growers use some form of VPD control already, without even knowing it. When you put clones under a dome, you’re keeping the RH high and the VPD low. This, in turn, slows transpiration to a crawl, greatly reducing the stress on the cuttings, which need time to form roots. Typically, most growers will keep their vegetativehumidity a little bit higher as well, which reduces stress.
Domes are a form of VPD control.
Most growers are concerned about the flowering cycle because that’s where the magic happens. You want to keep your VPD relatively high (low RH) during the flowering cycle. If you assume an average flowering cycle of 8 weeks, start with a moderate VPD (medium RH) during the first 3-4 weeks of your flowering cycle, then increase your VPD (lower your RH) towards the end of flowering. This reduces pathogenesis.
One thing you can do when a plant is stressed, say from moving from one room to another, is to raise the humidity. This lowers the transpirational stress and eases their transition into whatever phase or room you have set up. Additionally, HID lights can be stressful for plants, and VPD control gives you the ability to reduce their stress. If you have a dry environment and bright lights towards the top, you’ll see canopy leaves fold in like a taco. Plants do this to reduce light capture and reduce their internal temperature. If you see this happening, you need to ease up on the plants and reduce their stress.
CONCERNS WHEN USING VPD:
Pathogenesis is a big issue, which we’ve touched on briefly. The biggest drawback to running a low VPD (high RH) is that you can run into a lot of problems with pathogens if your rooms aren’t clean. As a result, many growers reduce their humidity as much as possible. Some growers brag that their humidity is as low as 20%, which is really bad for the plants and slows their growth.
Homogenizing a room’s environment is a struggle. In my experience, there are always new micro-environments forming in your room due to the nature of working with living organisms. Keeping on top of it all takes a lot of effort.
Good ventilation/circulation is necessary for VPD control.
Accurate sensor readings are also a problem I keep running into. Keeping the environment at your desired setpoint of temperature and humidity can be tricky. Having the right equipment and the right room layout can make a big difference.
WHAT EQUIPMENT DO YOU NEED TO EFFECTIVELY CONTROL VPD:
You’re going to need a humidifier for starters. You want to be able to inject humidity into the room without causing any problems such as being too close to one plant. If you have your humidifiers spraying plants directly with vapor, you will end up with undesirable microclimates which could favor pathogenesis. Personally, I think that ultrasonic humidifiers work best.
You are going to need a way to measure the leaf temperatures in order to accurately calculate VPD. This is where the online charts cause many growers problems and botrytisis becomes of real concern when not taking leaf temps into account. A simple $15 Infrared Temp gun will do the job quite well.
If you’re going to manage VPD, you’ll also want a controller that integrates your humidification and dehumidification systems. You want your controllers set up in such a way that when the lights are off, the humidification setpoints for the dehumidifiers are different if possible. An RH of 10-15% lower at night is ideal but not required.
Paying attention to RH after the lights go out is a big concern. As temperature drop the RH increases (ergo relative humidity) Slowing the temperature drop will aid in the dehumidifiers ability to keep the humidity in range. I would recommend checking humidity from 20-40 mins after lights out to ensure RH is not spiking.
Temperature are also important to control using a temp controller that controls both heating and cooling is ideal. This could be done by controlling fans, heaters, ac etc.
If you don't have all the fancy stuff listed you can still use VPD to to make adjustments to your setup that will improve the VPD for your stage of growth.
It’s important to note that plants are their own internal humidifiers, depending on how many plants are in a room and what stage of growth they’re at. Small plants have less surface area and transpire less. Small plants in a big room will require humidity injection to keep the humidity up, whereas plants at full size don’t need as much humidity injection because they’re already transpiring at an increased rate. When you hit the final stages of growth, you may have to run dehumidifiers to take water vapor out.
Realize that at this level you are doing some serious high performance fine-tuning of your gardening operation. You could be adding a few percent to the final weight of your yield, but it’s going to take some work and you are going to need the proper equipment to measure and control your garden at this level.
The fan system is required because we know botrytis and other fungi are always waiting to pounce. Botrytis establishes itself best between 50 and 70°F, in still air having humidity above 55%RH. We especially want to avoid condensation; this means watch out for uncontrolled temperature drops between daytime and night.
You will also need some type of computer system capable of running a modern spreadsheet program. This is not rocket surgery, but you (or someone you know) will need to know how to use some basic features of a spreadsheet. This is useful to display the logged files from a data acquisition setup, as well as for calculating VPDs and other moisture quantities. Consider it the entry stakes to quantifying and visualizing the performance of your growing operation.
Ideal KPA ranges for different stages of growth.
| Seedling/clone 0.4-0.8 Veg 0.8-1.1 Early flower 1-1.4 Late flower 1.3-1.5 |
Domes are a form of VPD control.
Most growers are concerned about the flowering cycle because that’s where the magic happens. You want to keep your VPD relatively high (low RH) during the flowering cycle. If you assume an average flowering cycle of 8 weeks, start with a moderate VPD (medium RH) during the first 3-4 weeks of your flowering cycle, then increase your VPD (lower your RH) towards the end of flowering. This reduces pathogenesis.
One thing you can do when a plant is stressed, say from moving from one room to another, is to raise the humidity. This lowers the transpirational stress and eases their transition into whatever phase or room you have set up. Additionally, HID lights can be stressful for plants, and VPD control gives you the ability to reduce their stress. If you have a dry environment and bright lights towards the top, you’ll see canopy leaves fold in like a taco. Plants do this to reduce light capture and reduce their internal temperature. If you see this happening, you need to ease up on the plants and reduce their stress.
CONCERNS WHEN USING VPD:
Pathogenesis is a big issue, which we’ve touched on briefly. The biggest drawback to running a low VPD (high RH) is that you can run into a lot of problems with pathogens if your rooms aren’t clean. As a result, many growers reduce their humidity as much as possible. Some growers brag that their humidity is as low as 20%, which is really bad for the plants and slows their growth.
Homogenizing a room’s environment is a struggle. In my experience, there are always new micro-environments forming in your room due to the nature of working with living organisms. Keeping on top of it all takes a lot of effort.
Good ventilation/circulation is necessary for VPD control.
Accurate sensor readings are also a problem I keep running into. Keeping the environment at your desired setpoint of temperature and humidity can be tricky. Having the right equipment and the right room layout can make a big difference.
WHAT EQUIPMENT DO YOU NEED TO EFFECTIVELY CONTROL VPD:
You’re going to need a humidifier for starters. You want to be able to inject humidity into the room without causing any problems such as being too close to one plant. If you have your humidifiers spraying plants directly with vapor, you will end up with undesirable microclimates which could favor pathogenesis. Personally, I think that ultrasonic humidifiers work best.
You are going to need a way to measure the leaf temperatures in order to accurately calculate VPD. This is where the online charts cause many growers problems and botrytisis becomes of real concern when not taking leaf temps into account. A simple $15 Infrared Temp gun will do the job quite well.
If you’re going to manage VPD, you’ll also want a controller that integrates your humidification and dehumidification systems. You want your controllers set up in such a way that when the lights are off, the humidification setpoints for the dehumidifiers are different if possible. An RH of 10-15% lower at night is ideal but not required.
Paying attention to RH after the lights go out is a big concern. As temperature drop the RH increases (ergo relative humidity) Slowing the temperature drop will aid in the dehumidifiers ability to keep the humidity in range. I would recommend checking humidity from 20-40 mins after lights out to ensure RH is not spiking.
Temperature are also important to control using a temp controller that controls both heating and cooling is ideal. This could be done by controlling fans, heaters, ac etc.
If you don't have all the fancy stuff listed you can still use VPD to to make adjustments to your setup that will improve the VPD for your stage of growth.
It’s important to note that plants are their own internal humidifiers, depending on how many plants are in a room and what stage of growth they’re at. Small plants have less surface area and transpire less. Small plants in a big room will require humidity injection to keep the humidity up, whereas plants at full size don’t need as much humidity injection because they’re already transpiring at an increased rate. When you hit the final stages of growth, you may have to run dehumidifiers to take water vapor out.
Realize that at this level you are doing some serious high performance fine-tuning of your gardening operation. You could be adding a few percent to the final weight of your yield, but it’s going to take some work and you are going to need the proper equipment to measure and control your garden at this level.
The fan system is required because we know botrytis and other fungi are always waiting to pounce. Botrytis establishes itself best between 50 and 70°F, in still air having humidity above 55%RH. We especially want to avoid condensation; this means watch out for uncontrolled temperature drops between daytime and night.
You will also need some type of computer system capable of running a modern spreadsheet program. This is not rocket surgery, but you (or someone you know) will need to know how to use some basic features of a spreadsheet. This is useful to display the logged files from a data acquisition setup, as well as for calculating VPDs and other moisture quantities. Consider it the entry stakes to quantifying and visualizing the performance of your growing operation.
HOW TO CALCULATE YOUR OWN VPD:
If you don't like math your in luck here is a formula you can put into a spreadsheet to do it for you. I use excel personally.
Enter the formula on the next line into spreadsheet cell A10 (copy and paste it).
=3.386*(EXP(17.863-9621/(A7+460))-((A6/100)*EXP(17.863-9621/(A5+460))))
You will type-in 3 values into 3 other cells:
Example:
Room temperature= 80°F
Room %RH= 47%
Assumed leaf temperature= 75°F
VPD= 1.34 kPa (a little too dry for best growth)
Calculating Individual Vapor Pressures
For those interested in further exploring water vapor pressure.
Enter the formula on the next line into spreadsheet cell A20 (copy and paste it).
=3.386*(A17/100)*EXP(17.863-9621/(A16+460)))
You will type-in 2 values into 2 other cells:
Examples:
1)
Room air temperature= 80°F
Room air %RH= 47%
Water vapor pressure= 1.67 kPa
2)
Leaf temperature= 75°F
%RH of the air inside the leaf = 100%
Water vapor pressure= 3.00 kPa
These 2 examples show the “long way” to calculate the VPD given in the VPD equation section above this one: Subtract the room condition from the leaf condition to come up with the room-to-leaf water vapor pressure deficit (3.00 – 1.67 = 1.33 kPa).
Ok well that the long/short version and I hope this helps. If ya have any questions I will do my best to answer
If you don't like math your in luck here is a formula you can put into a spreadsheet to do it for you. I use excel personally.
Enter the formula on the next line into spreadsheet cell A10 (copy and paste it).
=3.386*(EXP(17.863-9621/(A7+460))-((A6/100)*EXP(17.863-9621/(A5+460))))
You will type-in 3 values into 3 other cells:
- Cell A5: The air temperature (A5 in the formula)
- Cell A6: The air %RH (A6 in the formula)
- Cell A7: The leaf temperature (A7 in the formula)
Example:
Room temperature= 80°F
Room %RH= 47%
Assumed leaf temperature= 75°F
VPD= 1.34 kPa (a little too dry for best growth)
Calculating Individual Vapor Pressures
For those interested in further exploring water vapor pressure.
Enter the formula on the next line into spreadsheet cell A20 (copy and paste it).
=3.386*(A17/100)*EXP(17.863-9621/(A16+460)))
You will type-in 2 values into 2 other cells:
- Cell A16: The air temperature (A16 in the formula)
- Cell A17: The air %RH (A17 in the formula)
Examples:
1)
Room air temperature= 80°F
Room air %RH= 47%
Water vapor pressure= 1.67 kPa
2)
Leaf temperature= 75°F
%RH of the air inside the leaf = 100%
Water vapor pressure= 3.00 kPa
These 2 examples show the “long way” to calculate the VPD given in the VPD equation section above this one: Subtract the room condition from the leaf condition to come up with the room-to-leaf water vapor pressure deficit (3.00 – 1.67 = 1.33 kPa).
Ok well that the long/short version and I hope this helps. If ya have any questions I will do my best to answer
sandman83
Well-Known Member
they connect all the 5g buckets to a larger reservoir and run recirculating water instead of individuals. I found 10gal minimum for me to stay stable.
DirtyStrawHat
Active Member
i grabbed a brute!
https://www.homedepot.com/p/Rubbermaid-Commercial-Products-Brute-20-Gal-Grey-Round-Trash-Can-with-Lid-2031186/100211748
landlord didnt like it because im on second floor incase of a leak or spill.. so for now i have it in a new soup, same 5g cooler.. ph is 5.8 steady will update soon..
https://www.homedepot.com/p/Rubbermaid-Commercial-Products-Brute-20-Gal-Grey-Round-Trash-Can-with-Lid-2031186/100211748
landlord didnt like it because im on second floor incase of a leak or spill.. so for now i have it in a new soup, same 5g cooler.. ph is 5.8 steady will update soon..
DailyBlastin
Well-Known Member
i bought one of these 16gal barrels for my current setup, i also have 30gal and 55gal barrels from previous setups, they're real cheap, food grade, and look a hell of a lot better than a trash can lol
DirtyStrawHat
Active Member
update : ph 5.9,
almost zero water consumption lastnite through the night (back on regular light schedule now that timer issue is fixed)
ppm drop by 10
water 62
air 76
hum 30
going to let water temps rise to around 64 65 maybe i can get the plant to start drinking again
the wilt remains water level is raised a bit so benny can reach the top section of the roots and seem to be doing fine.. a closer inspection of the rootball once the subject was extracted revealed that the roots hadent been as slimy as first expected, but mostly stained from nute trickle. i sprayed that fucker down with the shower head anyway while i had the chance but still it looks the same. If there was any activity it was mostlikely directly under the netopt, i made a seperate container specifically for dumping dist water mixed with great white benny through the medium to further combat any activity in the proximity. This will now be the only thing getting dumped through the medium.
I think it will take a few days to achieve homeostasis once again. Now that the PH issue seems to be under control for the time being, maybe i can leave it alone for a few days without having to add anything.. I still am not ok with leaving the plant in the 5g res, by the size of the root system it could be a packed party by next week.. The old soup had an odd fog too it, along with alot of small root pieces. could the ph issue have been acid rain?
This user had a similar issue
almost zero water consumption lastnite through the night (back on regular light schedule now that timer issue is fixed)
ppm drop by 10
water 62
air 76
hum 30
going to let water temps rise to around 64 65 maybe i can get the plant to start drinking again
the wilt remains water level is raised a bit so benny can reach the top section of the roots and seem to be doing fine.. a closer inspection of the rootball once the subject was extracted revealed that the roots hadent been as slimy as first expected, but mostly stained from nute trickle. i sprayed that fucker down with the shower head anyway while i had the chance but still it looks the same. If there was any activity it was mostlikely directly under the netopt, i made a seperate container specifically for dumping dist water mixed with great white benny through the medium to further combat any activity in the proximity. This will now be the only thing getting dumped through the medium.
I think it will take a few days to achieve homeostasis once again. Now that the PH issue seems to be under control for the time being, maybe i can leave it alone for a few days without having to add anything.. I still am not ok with leaving the plant in the 5g res, by the size of the root system it could be a packed party by next week.. The old soup had an odd fog too it, along with alot of small root pieces. could the ph issue have been acid rain?
DWC: Day 30 of Flower PH dropping to 5.0 for NO reason
I'm an expert DWC grower and I've never really seen this before. I have 2 clones into different buckets and different tents and about 1 week ago the ph would drop to 5.0. I tried lowering the ppm from 1050 to 850 and the ph is still doing this. These are clones of clones and the previous batch...
www.rollitup.org
This user had a similar issue
DirtyStrawHat
Active Member
i like your setup, but that shit is double the price of the brute after shipping
DailyBlastin
Well-Known Member
doesnt have to be that exact one. heres a similar barrel on amazon for 29$ free shipping.
DirtyStrawHat
Active Member
thats not even bad, probably thicker plastic aswell..
DailyBlastin
Well-Known Member
Theyre just nice, im all for diying things but i like to diy with proper materials, anything i build i want to be as good as something you'd pay for in a specialty shop.
your next step should be dialing in your solution, PH and PPM meters are a must, also temperature plays a big role too, you wanna keep your solution between 65-70 ideally so depending on your area you will need either a water chiller, aquarium heater. or even both if your peak summer/winter temps demand. if you need a heater you're in luck, aquarium heaters are not that expensive, however if you need a water chiller be prepared to drop a few hundred even for the cheapest 1/10hp units.
DirtyStrawHat
Active Member
do you guys wash your hands before reaching in? ive heard nitrile gloves fuck ph also
DirtyStrawHat
Active Member
in a benny environment so without soap