New here, need help with DWC

[VBGrows]

Temp in res 21c

I was using Sensizym which is enzymes, u mean this? but I couldnt see any impact as I had other issues.

Right now I havent added it

 

[Sativa1970]

Maybe this will help you see what is really going on.PH in soil is different than hydro. Do you see how high PH is less of an issue in veg but magnifies in flower?

There are only two reason you need multiple bottles beyond veg and flower formulas. Overcoming a unique and temporary issue requires a short term boost, like silica during stretch. Second the manufacturer omitted/reduced an ingredient to increase sales of a supplement. They are all macro, micro and/or amino acids in different ratio with targeted advertising. If your PPM is stable and hydro tone neutral, the PH drifts cause, is in the bottle.

I use dynagrow foliage 9-3-6 and bloom 3-12-6 all in one formulas. Has all the micro and macro including calmag (AKA PH stabilizer, or dolomite) in one bottle. Ran 3rd gen clones side by side. GH, sensi, and dyna nutrients. No measurable difference in the three plants growth, yield or quality. It's cheap, easy to use and amazon or my local hydro shop carry it. Always recommend it as at least a good simple starting point for anyone new to DWC.

 

[VBGrows]

I had this chart that I was using as a guide, found it here in some post. Seems like this is off.

Will use that one, thanks!

I have checked the plant now, looking okayish, gave her some defoliation and removed affected leaves so I can properly see the difference next days.

Ph is 6.4 not adjusting it.

Thanks for all input and recommendations

 

[VBGrows]

I also have 2nd plant in DWC, which will be 30 days old tomorrow.

After topping (day 14), she couldnt recover + the ph issues.

But last few days she is looking better. Ph was 6.0 today. I was also adjusting ph for this plant previous weeks and probably it also affected its growth.

(2 others are in soil)

 

[Delps8]

I've read through bits and pieces of this thread and I don't have a clear picture of the grow environment.

At one point, your water temperature was 20° and your ambient temp was 21-24? Are those the values in your grown environment?

I didn't see a mention of humidity. Nutrient uptake is a highly impacted by temperature and humidity and that's because transpiration is a function of temperature and humidity.

What is the RH in the tent?

Light is what makes plants grow. If they're not betting much light, they can't manufacture much glucose so your plants will tend to grow more slowly than if they're getting more light. What lights are you using, what are the hang heights, the dimmer settings, and the lights on period?

What EC/PPM is your res?

How are you topping off your res and how much are you adding to your res on a daily basis?

Most nutrient issues are caused either by a mix up in mixing up the nutrients, by improper watering, or because temperature and RH are such that the level of transpiration is out of synch with the PPM of you fertilizer. Given that watering isn't an issue when growing in hydro, it's probably a question of how your nutes are mixed and/or your temperature + RH values are such that transpiration is too high/low so the chemicals in your fertilizer are being taken up in a way that's causing a nutrient imbalance.

 

[VBGrows]

I've read through bits and pieces of this thread and I don't have a clear picture of the grow environment.

At one point, your water temperature was 20° and your ambient temp was 21-24? Are those the values in your grown environment?

I didn't see a mention of humidity. Nutrient uptake is a highly impacted by temperature and humidity and that's because transpiration is a function of temperature and humidity.

What is the RH in the tent?

Light is what makes plants grow. If they're not betting much light, they can't manufacture much glucose so your plants will tend to grow more slowly than if they're getting more light. What lights are you using, what are the hang heights, the dimmer settings, and the lights on period?

What EC/PPM is your res?

How are you topping off your res and how much are you adding to your res on a daily basis?

Most nutrient issues are caused either by a mix up in mixing up the nutrients, by improper watering, or because temperature and RH are such that the level of transpiration is out of synch with the PPM of you fertilizer. Given that watering isn't an issue when growing in hydro, it's probably a question of how your nutes are mixed and/or your temperature + RH values are such that transpiration is too high/low so the chemicals in your fertilizer are being taken up in a way that's causing a nutrient imbalance.

Hey,

• Growbox temp 22-23c
• Res temp 21c
• Rh 45-55 (sometimes 60)
• Lights - ViparSpectra XS4000 (480 watt) - right now is hanging around 40cm from top bud sites, dimmed down to 75%
• 20/4 schedule, was running 24h for some time coz the temps went low but now its ok
• Last nut mix was around 1000 ppm
• Adding water to res: I fill water and keep it 24 hours in cold room for aeration. I add water around every 2 days, 5-6 liters which fills the res back to 14-15 liters. Ph’d 5.8

do you have good nute mixing order? For advanced nutrients?

 

[bluter]

which fills the res back to 14-15 liters. Ph’d 5.8

why are you ph'ing a product that is designed specifically not to be used with ph adjusters?
this is why the plants go sideways. i've gone back to the point constantly.

do you have good nute mixing order? For advanced nutrients?

calmag first, then the other nutes. h202 and enzyme cleaners last.

 

[VBGrows]

why are you ph'ing a product that is designed specifically not to be used with ph adjusters?
this is why the plants go sideways. i've gone back to the point constantly.





calmag first, then the other nutes. h202 and enzyme cleaners last.

I didnt ph’d product, i ph’d water im adding into the res because my tap water ph is 8.1

So u are saying I shouldnt even adjust tap water and add it into res?

mixing order:
-> root bosters after base?
-> Silica when and how?

 

[bluter]

I didnt ph’d product, i ph’d water im adding into the res because my tap water ph is 8.1

that is why your plants are suffering. you can't use a ph adjuster in the res at all.

empty the res and refeed everytime it gets low. never just add water. do not ph anything going into the res with that nute line.

So u are saying I shouldnt even adjust tap water and add it into res?

exactly. you can't use a ph adjuster at all with those nutes. throw the adjusters away or change nutes if you can't stop yourself.

mixing order:
-> root bosters after base?
-> Silica when and how?

calmag first.
boosters can be added after the base nutes. you have to make headroom for them in most nute schedules. simply adding a pk boost on top can be too hot for them.

never used silica in hydro as i found it threw too many other things out of balance.

 

[VBGrows]

that is why your plants are suffering. you can't use a ph adjuster in the res at all.

empty the res and refeed everytime it gets low. never just add water. do not ph anything going into the res with that nute line.




exactly. you can't use a ph adjuster at all with those nutes. throw the adjusters away or change nutes if you can't stop yourself.




calmag first.
boosters can be added after the base nutes. you have to make headroom for them in most nute schedules. simply adding a pk boost on top can be too hot for them.

never used silica in hydro as i found it threw too many other things out of balance.

Got it, now I understood more, thanks.

How low res water should empty for me to change? Below 50%? 75%?

 

[bluter]

Got it, now I understood more, thanks

go to the Advanced Nutrients site and read everything you can about that ph perfect line. try not to confuse it with the regular line. they label both the same, it's hard to tell which they are referring to.

 

[VBGrows]

go to the Advanced Nutrients site and read everything you can about that ph perfect line. try not to confuse it with the regular line. they label both the same, it's hard to tell which they are referring to.

I did that, I’ve read everything on their website I think

Im in this situation because when I started growing in DWC and bought equipment, I asked few questions to the shop owners and they said I still needed to adjust ph even with AN.

So welp, good that I posted it here lets see if I can recover the plant well with these tips,

Thanks again!

 

[bluter]

I did that, I’ve read everything on their website I think

did you notice they stress the product is not to be ph'd?

they are purposely vague on the topic. they say you can ignore ph but will not answer questions if you enquire about using a ph product with that line.

Im in this situation because when I started growing in DWC and bought equipment, I asked few questions to the shop owners and they said I still needed to adjust ph even with AN.

AN won't directly answer those questions, how would the shop owners know any different? the shop owners want to sell product and can only give you anecdotal advice based on their perspective.

So welp, good that I posted it here lets see if I can recover the plant well with these tips

it won't be wasted money. i'd run another nute line though if you stay in active hydro. the ph perfect can be used quite successfully in passive hydro and soil apps. it's active hydro where that line falls flat on its face.

 

[Sativa1970]

Strange how your chart has P and Ca flipped.

According to AN sight;
PH perfect is cleated with cations and anions. As the PH increases cations are broken free from the nutrient lowering the PH. "PH perfect is designed to work best with RO water but any low mineral water can be used." " Average low mineral water is PH7." There are enough cations for "PH control up to 10-14 days."

PH7 is 10X more acidic than PH8 in a logarithmic formula. There are enough cations to drop the PH 1 point, from 7 to 6 and then maintain minor adjustment for 10 days. Starting at PH of just 8 would require 10X more cations to buffer and PH9 would be 100x more. Using the cleated cations to buffer initial water depletes the buffering. Nutrients precipitate out of solution at PH8. There molecular formula is proprietary but chemistry is universal. There are only 2 possibilities for the precipitate reaction over PH8. Cleat bond breaks releasing all cations (most likely) or cleat forms a double bond binding cation out of solution. Starting at a PH over 7 or expecting it to hold more than 2 weeks is beyond this products capability. The reason it isn't holding PH is that the cations are depleted. This is why you are adding more in the form of PH down. Dropping too low will release the cleated anions. Too low is undefined with unstable cation ratio so PH7 could become the new, too low. This is why they do not recommend manual adjustment.

The real issue is what is depleting the cations that causes the rise in PH? Starting PH depletion? Excess anions in water or clay? Roots absorb both and release the opposite back into the water. P is the only macro anion absorbed and released as cation. N K Cal and mag are cations but roots convert them into anions. This is how having one nutrient in excess can effect the PH.

If you start neutral and maintain the correct PPM for the plant, the PH should never shift anyway. PH is an indicator that something else is wrong. Buffering or adding PH up and down is like clearing the check engine light without fixing the cars problem. Still a problem and the light will just turn back on.

Can you take an EC reading? PPM are not universal so only good for determining a shift in nutrient from day to day. EC is a quantified value.

The plants look 10x better since you started.

 

[bluter]

i think you mean chelate and not cleat .... it is football season lol

edit: also if ph drifts it can't be fixed with a ph adjuster in the ph perfect nute line. it interacts with the nute causing the problems seen here. what you get is what you get.

 

[VBGrows]

UPDATE:
Pink Love Poison Auto - Day 58
Strawberry Gorilla Auto - Day 31

They are doing much better after stopping ph adjustments.

Today I changed the reservoir for Strawberry Gorilla, I gave:
Calmag 2ml/2
Micro, grow, bloom 2ml/2
Piranha 2ml/2
Voodoo Juice 2ml/2
it came out 800ppm, 2.2 EC, 6.6 pH

I'm planning to change the reservoir for the Pink Love Poison, it was around 50% today.

But I have checked the EC and it shows 3.1, 1130ppm, ph 6.3.

PPM has increased from the last time by around 100, but isn't EC a bit high?

Also, THANKS EVERYONE for the input, and especially @bluter!

 

[bluter]

they do look a pile better. if ec increases it's drinking more than eating.

you may find this useful :

unfortunately, you can't use the ph info as a guide with it as the nute you use does not work that way. the rest remains relevant though.

if you had a proper hydro nute that used ph the correct way you could use that chart as bible.

 

[VBGrows]

they do look a pile better. if ec increases it's drinking more than eating.

you may find this useful :

unfortunately, you can't use the ph info as a guide with it as the nute you use does not work that way. the rest remains relevant though.

if you had a proper hydro nute that used ph the correct way you could use that chart as bible.

Yeah, I already saved this, will decrease EC from next feeding.

 

[Delps8]

Hey,

• Growbox temp 22-23c
• Res temp 21c
• Rh 45-55 (sometimes 60)
• Lights - ViparSpectra XS4000 (480 watt) - right now is hanging around 40cm from top bud sites, dimmed down to 75%
• 20/4 schedule, was running 24h for some time coz the temps went low but now its ok
• Last nut mix was around 1000 ppm
• Adding water to res: I fill water and keep it 24 hours in cold room for aeration. I add water around every 2 days, 5-6 liters which fills the res back to 14-15 liters. Ph’d 5.8

do you have good nute mixing order? For advanced nutrients?

No experience with AN.

Re mixing order - silica supplements first then follow the manufacturer's directions.

Many growers add CalMag when it's not called for by the nutrient manufacturer. I don't see that as a wise approach to growing healthy plants.

Your grow environment is "cold and damp". Some growers here on 420 "don't believe" in VPD which is a measurement used in the agricultural world to understand how much plants are transpiring. Given that transpiration is plays a major role in the health of a plant, it's the standard mechanism when discussing temperature and humidity.

Vapor pressure deficit is a way of using one number to define a range of temperature and humidity values. It's handy because physics tells us that the rate at which water leaves a plant is the same 21° and 52% as it is at 28° and 62%.

At 22° and 50%, your plants are suffocating. The Vapor Pressure Deficit ("VPD") is 0.69. From the attached screenshot, you can see that your plants are in an environment that is more humid than they should be in seedling stage.

Seedlings need to be in a humid environment because they don't have the root structure needed to take in water. As plants mature, the root system matures and the air in which they're growing should be less humid. The lower humidity allows plants to transpire more (giving off moisture) which, in turn requires them to take up more moisture via the root system.

About 50% of nutrients flow into a plant due to the water taken in to replace the water lost due to transpiration. When your environment is so cold and wet, water can't leave the plant and the vapor pressure deficit (the difference in the amount of water in the plant vs the water in the air) is low. Nutrient imbalances are common when VPD is so far out of range.

In addition to causing nutrient issues, the low temperature tends to inhibit growth. The rate or photosynthesis is highly dependent on ambient temps. At your current temps, the rate of photosynthesis is about ½ of what is would be if you were to raise the ambient temp to just 25°. If you were to raise temps to 30, you would see even greater improvement in growth.

The graphic below is from "Photosynthetic response of Cannabis sativa L. to variations in photosynthetic photon flux densities, temperature and CO2 conditions" Chandra et al 2008

Re. the chart that's floating around. My best advice is to disregard it completely. As a new grower, I was quite taken by it and, when my pH dropped, I spent hours emptying my res and adding back nutes of lower strength. If you read through my early grow journals, I've detailed the trials and tribulations I (needlessly) put myself through following the advice of the chart.

I was quite fortunate that a member of this forum, who hasn't posted in some years, PM'd me an explained that it was perfectly normal for a res to drop pH in flower and he was kind enough to explain why that happens.

The chart in question was put together by a grower in a forum in the UK back in 2012 and, while it is based on observation and deduction, it is, unfortunately, not based on how plants function. Someone with an A level in chemistry or plant biology would understand the problems with it. In many cases following its guidance will have a positive outcome but the underlying erroneous assumption is that EC/PPM changes are indicators of the chemical makeup of a nutrient solution and that is absolutely false. It's commonly taken as such, I understand that, but it is simply incorrect.

In a res as small as yours some nutrients are taken out of solution in a matter of hours yet EC does not change. Conversely, many nutrients are taken up out of solution before any change in EC is registered because the chemicals that cause the significant change in EC are taken up very slowly.

PPM is a calculation based on the electrical conductivity of a solution. It tells you nothing about the chemical makeup of the nutrients in your res. As soon as nutrient solution is poured into a res that has plants in it, the chemical composition of the nutrient solution will change but it may be days before the EC changes.

The easiest approach to res management is either to top off with RO water and change the reservoir when PPM has fallen a certain amount or top off with nutrient solution that is EC 1.2

If you're interested in either of those two methods, please let me know and I'll upload PDF's on reservoir management that will provide some insight into how things work.

I'm not arguing that things won't work out by following "The Wonder Chart", as I've dubbed it. I even found a graphic that I dubbed "Son on of Wonder Chart". Fortunately, things won't go particularly wrong by following the advice (A broken clock is correct twice a day) but they're based on observation and deduction rather than working from basics of plant biology and chemistry so they will, eventually, take you into a blind alley. That's what happened to me but I was fortunate to have someone here on 420 help me resolve the issue that I was facing.

Oh, in one posting you said that you were at EC 3.1 and PPM was 1100± or somesuch. PPM is calculated from EC and is expressed on the 500 scale and the 700 scale but there is one other scale used for a PPM calculation but the details elude me at the moment. Under the 500 or 700 conversion values, EC 3.1 will be at least 1550.

In addition to having a very cold and wet (high RH) environment, the level of fertilizer that you're giving your plants is extremely high. My grow, link in the sig block, is up to EC 1.66 which is the highest it has been through the entire grow.

I raise these points because EC 3.1 ≠ 1100±PPM (you might want to check your meter) and at 3.1 and a VPD of 0.7±, nutrient issues are no surprise.

Drop your EC to 1.5±, drop your RH and increase your ambient temp until your VPD is about 1.0 (veg) or 1.2-1.5 (flower). As it stands, you're growing your plants in fog.

 

[VBGrows]

No experience with AN.

Re mixing order - silica supplements first then follow the manufacturer's directions.

Many growers add CalMag when it's not called for by the nutrient manufacturer. I don't see that as a wise approach to growing healthy plants.

Your grow environment is "cold and damp". Some growers here on 420 "don't believe" in VPD which is a measurement used in the agricultural world to understand how much plants are transpiring. Given that transpiration is plays a major role in the health of a plant, it's the standard mechanism when discussing temperature and humidity.

Vapor pressure deficit is a way of using one number to define a range of temperature and humidity values. It's handy because physics tells us that the rate at which water leaves a plant is the same 21° and 52% as it is at 28° and 62%.

At 22° and 50%, your plants are suffocating. The Vapor Pressure Deficit ("VPD") is 0.69. From the attached screenshot, you can see that your plants are in an environment that is more humid than they should be in seedling stage.

Seedlings need to be in a humid environment because they don't have the root structure needed to take in water. As plants mature, the root system matures and the air in which they're growing should be less humid. The lower humidity allows plants to transpire more (giving off moisture) which, in turn requires them to take up more moisture via the root system.

About 50% of nutrients flow into a plant due to the water taken in to replace the water lost due to transpiration. When your environment is so cold and wet, water can't leave the plant and the vapor pressure deficit (the difference in the amount of water in the plant vs the water in the air) is low. Nutrient imbalances are common when VPD is so far out of range.

In addition to causing nutrient issues, the low temperature tends to inhibit growth. The rate or photosynthesis is highly dependent on ambient temps. At your current temps, the rate of photosynthesis is about ½ of what is would be if you were to raise the ambient temp to just 25°. If you were to raise temps to 30, you would see even greater improvement in growth.

The graphic below is from "Photosynthetic response of Cannabis sativa L. to variations in photosynthetic photon flux densities, temperature and CO2 conditions" Chandra et al 2008

Re. the chart that's floating around. My best advice is to disregard it completely. As a new grower, I was quite taken by it and, when my pH dropped, I spent hours emptying my res and adding back nutes of lower strength. If you read through my early grow journals, I've detailed the trials and tribulations I (needlessly) put myself through following the advice of the chart.

I was quite fortunate that a member of this forum, who hasn't posted in some years, PM'd me an explained that it was perfectly normal for a res to drop pH in flower and he was kind enough to explain why that happens.

The chart in question was put together by a grower in a forum in the UK back in 2012 and, while it is based on observation and deduction, it is, unfortunately, not based on how plants function. Someone with an A level in chemistry or plant biology would understand the problems with it. In many cases following its guidance will have a positive outcome but the underlying erroneous assumption is that EC/PPM changes are indicators of the chemical makeup of a nutrient solution and that is absolutely false. It's commonly taken as such, I understand that, but it is simply incorrect.

In a res as small as yours some nutrients are taken out of solution in a matter of hours yet EC does not change. Conversely, many nutrients are taken up out of solution before any change in EC is registered because the chemicals that cause the significant change in EC are taken up very slowly.

PPM is a calculation based on the electrical conductivity of a solution. It tells you nothing about the chemical makeup of the nutrients in your res. As soon as nutrient solution is poured into a res that has plants in it, the chemical composition of the nutrient solution will change but it may be days before the EC changes.

The easiest approach to res management is either to top off with RO water and change the reservoir when PPM has fallen a certain amount or top off with nutrient solution that is EC 1.2

If you're interested in either of those two methods, please let me know and I'll upload PDF's on reservoir management that will provide some insight into how things work.

I'm not arguing that things won't work out by following "The Wonder Chart", as I've dubbed it. I even found a graphic that I dubbed "Son on of Wonder Chart". Fortunately, things won't go particularly wrong by following the advice (A broken clock is correct twice a day) but they're based on observation and deduction rather than working from basics of plant biology and chemistry so they will, eventually, take you into a blind alley. That's what happened to me but I was fortunate to have someone here on 420 help me resolve the issue that I was facing.

Oh, in one posting you said that you were at EC 3.1 and PPM was 1100± or somesuch. PPM is calculated from EC and is expressed on the 500 scale and the 500 scale but there is one other scale used for a PPM calculation but the details elude me at the moment. Under the 500 or 700 conversion values, EC 3.1 will be at least 1550.

In addition to having a very cold and wet (high RH) environment, the level of fertilizer that you're giving your plants is extremely high. My grow, link in the sig block, is up to EC 1.66 which is the highest it has been through the entire grow.

I raise these points because EC 3.1 ≠ 1100±PPM (you might want to check your meter) and at 3.1 and a VPD of 0.7±, nutrient issues are no surprise.

Drop your EC to 1.5±, drop your RH and increase your ambient temp until your VPD is about 1.0 (veg) or 1.2-1.5 (flower). As it stands, you're growing your plants in fog.

Thanks for taking time to write this big comment, I really appreciate it.

Ive heard about VPD but havent really used it to calculate the outcome, but as of now, after your comment, it seems more understandable.

I was already planning to decrease the EC of the nute mix and will change the res tomorrow. I dont have access to RO water, so the first option u mentioned wont help me.

And with the top off, I had recommendation here not to top off with anything and just change the reservoir, but would be happy to receive any other advices so please drop the pdf u were talking about.

Last time Rh was around 45 (few days ago), I think I can increase the box temp to 25-26, but Im concerned that might increase temp in the reservoir as well and that might become a problem, but will try. For dropping rh, possibly need dehumidifer, I have good air circulation in the box but it doesnt decrease the rh much. The EC for sure, already was planning to decrease from the next feeding, which is tomorrow.

About the meters, I think my ppm meter is off, was using it for quite some time, EC meter is new so possible I was calculating ppm wrongly with the bad meter.