Top growth is yellowing heavily, what's the cause?

[Acid]

Hey guys,

So it's been around 8 years since I last posted. I spent around 50 bucks for everything back then, built pretty much everything myself, and ended up with almost 6oz of bud. No pH testing, literally nothing. I risked it all and you guys helped me, and now I need your help again. 8 years ago was my first grow, now this is my second. I learned tons of stuff, but this time I'm a bit clueless again.

First of all, some general info:

• 150W MarsHyrdo TS1000 at 60cm height, 100% light
• Autoflower Orion F1
• 25L fabric pots filled with ~20L each, soil temperature at around 20-21°C. I thought 50L of soil would fill up two 25L pots, but I guess I'm just.. dumb. Oh well.
• BioBizz Allmix (Soil)
• BioBizz nutrient line
• Day 29 of veg, apparently starting to flower now
• pH at around 6.8
• Humidity / Temp: 50-55% (night 55-65%), 24-26°C daytime (18-21°C night)
• Topped around 10 days ago, no problems, new growth is good. Some LST done.
• Airflow is fine, nothing high end, but intake on bottom and hot air out the top with another fan. Air movement is 100% there.
• Pots are raised slightly to have better air circulation on the bottom.
• Both plants show the same problems on top

Yesterday I gave the first flowering feeding, including TopMax, Bloom, Grow & CalMag, normal recommended dose for autoflowers. pH still at around 6.8, PPFD at 590-620. This problem appeared around 5 or 6 days ago. I have some hope that it was just some kind of deficiency, as I only fed it half a dose of Fishmix until now, because the Allmix was rather hot by itself. They grew wonderfully, if maybe too slowly because I had a few pests as I went from outdoor to indoor, they're all done now though (BT and neem, also nematodes and yellow traps, I'm clear now).

I'm by no means a professional, I'm a total beginner. I just ordered a high quality pH meter which will probably arrive monday or tuesday, because I don't trust the $20 one anymore. I feel like the pH is too high, and I got some kind of lock-out, but I'm not 100% sure and I want to ask you guys too.

I trust all of you, you guys are the only community that's non jugdemental & just wants to help, please help me once again.

 

[Phytoplankton]

Your PH meter may help in diagnosis, but just from the pics it looks lik it could be an iron deficiency, do any of your nutes/micronutes contain iron? An input PH above 6.5 can inhibit iron uptake. When you get your meter try to ph your water/nutes at about 6.2.

 

[Buds Buddy]

Hey guys,

So it's been around 8 years since I last posted. I spent around 50 bucks for everything, built pretty much everything myself, and ended up with almost 6oz of bud. No pH testing, literally nothing. I risked it all and you guys helped me, and now I need your help again. 8 years ago was my first grow, now this is my second. I learned tons of stuff, but this time I'm a bit clueless again.

First of all, some general info:

• 150W MarsHyrdo TS1000 at 60cm height, 100% light
• Autoflower Orion F1
• 25L fabric pots filled with ~20L each, soil temperature at around 20-21°C
• BioBizz Allmix (Soil)
• BioBizz nutrient line
• Day 29 of veg, apparently starting to flower now
• pH at around 6.8
• Humidity / Temp: 50-55% (night 55-65%), 24-26°C daytime (18-21°C night)
• Topped around 10 days ago, no problems, new growth is good. Some LST done.
• Airflow is fine, nothing high end, but intake on bottom and hot air out the top with another fan. Air movement is 100% there.
• Pots are raised slightly to have better air circulation on the bottom.
• Both plants show the same problems on top

Yesterday I gave the first flowering feeding, including TopMax, Bloom, Grow & CalMag, normal recommended dose for autoflowers. pH still at around 6.8, PPFD at 590-620. This problem appeared around 5 or 6 days ago. I have some hope that it was just some kind of deficiency, as I only fed it half a dose of Fishmix until now, because the Allmix was rather hot by itself. They grew wonderfully, if maybe too slowly because I had a few pests as I went from outdoor to indoor, they're all done now though (BT and neem, also nematodes and yellow traps, I'm clear now).

I'm by no means a professional, I'm a total beginner. I just ordered a high quality pH meter, because I don't trust the $20 one anymore. I feel like the pH is too high, and I got some kind of lock-out, but I'm not 100% sure and I want to ask you guys too.

I trust all of you, please help me once again.

For most soils the pH of the nutes should be in the 6.3 area. Pro Mix & Bio Bizz I think are different, but not sure.
@SmokingWings probably knows.

 

[Phytoplankton]

For most soils the pH of the nutes should be in the 6.3 area. Pro Mix & Bio Bizz I think are different, but not sure.
@SmokingWings probably knows.

According to BioBuzz a PH of 6.2-6.3 (I had to look it up).

 

[Roy Growin]

Is your base water very high pH? If it is, add a drop of lemon juice and it should get you somewhere nearer to pH 6.0-6.5
Plants that size can probably handle 3ml/L Gro/Bloom
AlgaMic is also recommended in the mix

 

[Acid]

Here are some more images I just took.

I don't know the exact pH of the tapwater right out of the tap, but the official pH of my towns tapwater, measured by the sanitary district, is a straight 8, which seems indeed a bit high.

Most important question right now - I will probably get the good pH meter (Around 80 bucks this time) on monday or tuesday. Will my plants be in huge danger by then? Or can I save them? And if it's a ph lockout, will I need to flush them fully before fixing the pH? I know I'll probably have to do a 24h slurry test with the pH meter, which is what I'll prepare the day before arrival of the meter itself.

As I said, second grow, this time with more severe problems. I'm totally clueless about pH problems, as I haven't had them back then, with the same tapwater and rather bad old soil. It was just luck I guess.

 

[CaptainLucky]

Here are some more images I just took.

I don't know the exact pH of the tapwater right out of the tap, but the official pH of my towns tapwater, measured by the sanitary district, is a straight 8, which seems indeed a bit high.

Most important question right now - I will probably get the good pH meter (Around 80 bucks this time) on monday or tuesday. Will my plants be in huge danger by then? Or can I save them? And if it's a ph lockout, will I need to flush them fully before fixing the pH? I know I'll probably have to do a 24h slurry test with the pH meter, which is what I'll prepare the day before arrival of the meter itself.

As I said, second grow, this time with more severe problems. I'm totally clueless about pH problems, as I haven't had them back then, with the same tapwater and rather bad old soil. It was just luck I guess.

Are you reusing your soil from your last grow? CL

 

[Acid]

Are you reusing your soil from your last grow? CL

My last grow was almost 9 years ago, that'd be funny. It's BioBizz Allmix, freshly bought before I started this one

 

[CaptainLucky]

My last grow was almost 9 years ago, that'd be funny. It's BioBizz Allmix, freshly bought before I started this one

I don’t assume anything and if you don’t ask then you don’t know right? lol CL

 

[Phytoplankton]

Here are some more images I just took.

I don't know the exact pH of the tapwater right out of the tap, but the official pH of my towns tapwater, measured by the sanitary district, is a straight 8, which seems indeed a bit high.

Most important question right now - I will probably get the good pH meter (Around 80 bucks this time) on monday or tuesday. Will my plants be in huge danger by then? Or can I save them? And if it's a ph lockout, will I need to flush them fully before fixing the pH? I know I'll probably have to do a 24h slurry test with the pH meter, which is what I'll prepare the day before arrival of the meter itself.

As I said, second grow, this time with more severe problems. I'm totally clueless about pH problems, as I haven't had them back then, with the same tapwater and rather bad old soil. It was just luck I guess.

Your plants will survive, and after you get the issues ironed out (pun intended) the color may return to the leaves (but it might not). Biobuzz is a peat base mix, it also already has nutes in it (Not sure about Biobuzz light). A slurry test probably won't help you with anything. For starters, just ph you water to 6.2

Edit: The reason I say just start with PHing the input water is twofold, first it's cheap and easy, the other reason is: Do one thing at a time, if you change too many things at once, you wont know what worked, and what didn't, plus if you do too many things some may be antagonistic or self cancelling.

 

[Acid]

Your plants will survive, and after you get the issues ironed out (pun intended) the color may return to the leaves (but it might not). Biobuzz is a peat base mix, it also already has nutes in it (Not sure about Biobuzz light). A slurry test probably won't help you with anything. For starters, just ph you water to 6.2

Edit: The reason I say just start with PHing the input water is twofold, first it's cheap and easy, the other reason is: Do one thing at a time, if you change too many things at once, you wont know what worked, and what didn't, plus if you do too many things some may be antagonistic or self cancelling.

So don't flush, none of that, just ph the tapwater with nutes included and check what the ph is? And if it's too high, add a ph-low?

 

[Phytoplankton]

So it's been around 8 years since I last posted. I spent around 50 bucks for everything back then, built pretty much everything myself, and ended up with almost 6oz of bud. No pH testing, literally nothing.

The reason you may not of had problems 8 years ago is that municipal water supplies change often, new wells or water sources can be added or deleted and change the chemistry of the water being supplied. Not only that most muni water suppliers artificially increase the PH to alkaline, as it helps keep the pipes from corroding.

 

[Buds Buddy]

The reason you may not of had problems 8 years ago is that municipal water supplies change often, new wells or water sources can be added or deleted and change the chemistry of the water being supplied. Not only that most muni water suppliers artificially increase the PH to alkaline, as it helps keep the pipes from corroding.

Since the bottom of the plants look healthy & the yellowing is at the top & I'm seeing pistils couldn't this be the start of a "P" def. ?

 

[Regrowth]

Plants turn yellowish at the top when they first enter flower.
In fact, you can kind of use it as an indicator that they've started flowering even before pistils form.
Cheers.

 

[Phytoplankton]

Since the bottom of the plants look healthy & the yellowing is at the top & I'm seeing pistils couldn't this be the start of a "P" def. ?

P & K deficiencies start with the oldest leaves first (bottom up), iron and several other non-mobile nutrient deficiencies start with the newest leaves. I still believe it stems from the 8.0 ph of the input water. Iron doesn't absorb well at that ph, and may even be locking out in solution. Not saying it couldn't be a different micronute, but that kind of yellowing on new growth is not normal.

 

[Wastei]

Without any data regarding your source water your guess is as good as mine? I would stop using Topmax and Calmag at the same time, you will only worsen the Ca:Mg ratio. Topmax contain Mg and you don't want to add more to what's already in Grow, Bloom and Calmag.

 

[Acid]

Without any data regarding your source water your guess is as good as mine? I would stop using Topmax and Calmag at the same time, you will only worsen the Ca:Mg ratio. Topmax contain Mg and you don't want to add more to what's already in Grow, Bloom and Calmag.

I'm really sorry for not being able to provide any detailed information, as I'm tight on money, trying my best to get some equipment ready to see what's wrong. I know it's my own fault, but I guess I just like to risk it.

And thanks a lot for the topmax / calmag tip, should I leave out calmag, or topmax?

 

[Roy Growin]

I'm really sorry for not being able to provide any detailed information, as I'm tight on money, trying my best to get some equipment ready to see what's wrong. I know it's my own fault, but I guess I just like to risk it.

And thanks a lot for the topmax / calmag tip, should I leave out calmag, or topmax?

You don't need CaMg in AllMix; TopMax is for when they start to fully flower

 

[Wastei]

You don't need CaMg in AllMix; TopMax is for when they start to fully flower

Topmax is just some fulvic acid and Epsom salt. Biobizz is otherwise pretty low in Mg.

0.5g Epsom salt per gallon of water is a way better deal and will last you years instead of a cycle or two.

I would start adding "Calmag" in mid to late flower if it's low in Nitrogen. That's usually when the lime start to be all used up in the medium.

 

[Regrowth]

Off topic but your light should be 12-14" away.