pH Dropping..

inthetrees

Active Member
Been a while since I posted this topic but I recently found out what my problem was. I wanted to share just incase someone else reads my previous comments and goes down the wrong path... I was making 3 mistakes that were locking out my systems.

First error was running Potassium Silicate. After learning about Monosilicic I will never run Potassium Silicate again. It was raising my pH too much and in turn i was having to add a substantial amount of pH down to counteract. As stupid as it sounds I never thought to compensate for the Potassium either.

Second error was switching out the Remo Astroflower (PK Booster) for Liquid Koolbloom. I was able to resolve my issues briefly but the pH and ppm fluctuations kept getting out of hand. The only thing that would give me a day or 2 of peace was doing a full system flush.

Few days ago I cut out the Koolbloom and went back to the Astroflower. What i didn't realize was that the koolbloom was x2 as strong ppm wise compared to the astroflower. Not only was the silicate adding extra Potassium, so was the koolbloom.

Once i switched back to the full Remo line the pH stabilized, however the ppms kept rising signalling the solution was too strong (800 ppm). After dicking around for a week I have both my systems at 400 ppm @ the end of week 7. I'm finally seeing the ppms dropping and pH drifting slightly and the plants are responding much better obviously.

Last issue was using a cheap ebay ppm meter that I never had calibrated. I recently got a proper Bluelab EC meter and it turns out my ebay unit was reading over 200 ppm higher.

Hope this info helps someone down the road...

-itt
 

Greenthumbskunk

PICK YOUR OWN
Hey guys,

Wondering if anyone has had any pH issues in UC/RDWC when going from veg to flower? I was feeding 800ppm in veg and things were perfect. pH was drifting up, plants were drinking a ton, ppm's were slowly dropping.

I lollipopped and cleaned the canopy the day I flipped and it was business as usual for the next two weeks. I then did another clean up and the end of week 2. Then things kinda got weird after that...Everything flipped upside down.

pH started dropping, ppms rising. Plants were drinking but went from 6 - 8 gallons per day down to 4. I figured this was from removing so much of the bottom growth. Less plants = less nutes needed. As per the chart posted on here, those signs were pointing towards the nutrient solution being too high. I flushed the systems and dropped to 650 ppm. PPm's dropped about 50 -60 and ph rose slightly all within 4 hours, then it was back to ph dropping and ppms rising. Ph would drop from 5.7 to 4.7 overnight. I adjusted the pH upwards for 2 days then said screw it and flushed again this time dropping to 500 ppm.

Once again the systems dropped 50 - 60 ppm in the first few hours and the cycle started again. It's slower this time now. lights went out and pH was 6.2, woke up to 6.1 and ppms from 460 to 430. Now the ppms seem to be dropping ever so slightly however the pH is creeping down.

I'm at a loss as to what's going on. I've spent the last week going over every single thread on every forum trying to find an answer. There are quite a few people who have experienced the exact same thing as I am seeing. Everything fine in veg, high ppms, then 2 or 3 weeks into flower it all crashes and the plants want half of what they were eating before. I haven't found a solid answer though. There's been a few guys saying that its a salt buildup and to flush the systems with straight water for 24 - 48 hours but to me that doesn't make sense. Where would the salt build up be? I've flushed the systems every 7 - 10 days. It's UC not soil. Everything points to root rot or pythium but I'm running DIY Uc Roots @ 7ml/gal and adding in more every 3-4 days. My water temps are also at 66F. Environment has been static with canopy temp @ 82-85F, ambient room @ 75F and Humidity @ 65%. My roots have a brown tinge but its a stain from the nutes. There's no slime, gunk on bulkheads, or bad smell.

The only thing I've been not been able to control is cooling the room at night. I got a 50 pint dehumidifier and it will drop the room to 45% but the heat is keeping the overnight temps at 75F. I'm just waiting on a 6" damper to show up so I can setup a fresh air intake/exhaust with a temp controller for lights off. Aside from that nothing has changed.

I'm lost as to how these plants were eating 800+ ppms in the systems and the top offs at 1100 ppm to compensate, yet now I have the systems and top offs @ 500 going into week 4 and the pH is still dropping a bit. I could keep compensating by adding pH up but I feel like thats just a bandaid and I want to know wtf is going on or what has changed. I'm going to see how things so over the next 24 hours, but if I see a ph drop over the next 24 hours all I can think to do is drop down more. I have 2 separate systems with 2 different strains experiencing the exact same thing. Idk wtf else to do.

I have always experienced the plants after stretch didnt need as much nutes or drank as much unless you have low humidity levels.
I used to grow in 1200 ppm levels but have slowly reduced that down to around 500. Ive been dealing with brown algea for months now and thats been a battle.
Very depressing. Havent sold anything in months
 

inthetrees

Active Member
Damn sorry to hear about the algae :(

What your saying is right on point with what I experienced... Soon as I was done stretch it was like I hit a wall and the plants wanted way less. Granted I had locked my systems right up by adding the excess Potassium from the Silicate. Even after I figured out what I did wrong, the plants leveled out at about 350 ppm for the last few weeks whereas I read of guys running over 1000+ in an RDWC setup. Enviro and strain obviously play a huge factor, but coming from soil I couldn't believe that they needed so little.

I also grew from beans so I had some pheno's that were burnt to shit and others that were lush and taking it all in...

This round I'm running half the ppms I was prior and plan to top out at 500 - 600 rather than pushing the envelope. I'll see what the EC does though lol. Maybe Current Culture's EC recommendations aren't bullshit lmfao.

Hope you get your issues sorted out mang!
 

Streetpro09

Tester
Damn sorry to hear about the algae :(

What your saying is right on point with what I experienced... Soon as I was done stretch it was like I hit a wall and the plants wanted way less. Granted I had locked my systems right up by adding the excess Potassium from the Silicate. Even after I figured out what I did wrong, the plants leveled out at about 350 ppm for the last few weeks whereas I read of guys running over 1000+ in an RDWC setup. Enviro and strain obviously play a huge factor, but coming from soil I couldn't believe that they needed so little.

I also grew from beans so I had some pheno's that were burnt to shit and others that were lush and taking it all in...

This round I'm running half the ppms I was prior and plan to top out at 500 - 600 rather than pushing the envelope. I'll see what the EC does though lol. Maybe Current Culture's EC recommendations aren't bullshit lmfao.

Hope you get your issues sorted out mang!
Just another perspective. It's my first run with a RDWC setup so these are just observations at this point. My plants are about two weeks into strech and they are really liking 600 ppm. That's all I have for now.
 

Armdog

RDWC GROWER
Just another perspective. It's my first run with a RDWC setup so these are just observations at this point. My plants are about two weeks into strech and they are really liking 600 ppm. That's all I have for now.
I run 4 site RDWC and if I go over 380 to 450 ppm I have problems. I run koolbloom during flower , I flip at week 4 of veg and start koolbloom at week 5. Just a note:. I use General Hydroponics 3 part and only use it at 1/3 recommend.
 

Streetpro09

Tester
I run 4 site RDWC and if I go over 380 to 450 ppm I have problems. I run koolbloom during flower , I flip at week 4 of veg and start koolbloom at week 5. Just a note:. I use General Hydroponics 3 part and only use it at 1/3 recommend.
Are you asking for help or just telling me about your stuff?
 

inthetrees

Active Member
I'm seeing the same numbers this round as I did the last one, even with different strains. I'll top out at 800 and soon as stretch is over they are down to 600 - 650. Saves me allot on nute costs lol
 

inthetrees

Active Member
Pretty crazy reading some of the old threads on the current culture setups... Documented grows of some guys never going over 300 while others pushing up to 1300 - 1500. Obviously a pile of variables but quite the differential.
 

Streetpro09

Tester
Pretty crazy reading some of the old threads on the current culture setups... Documented grows of some guys never going over 300 while others pushing up to 1300 - 1500. Obviously a pile of variables but quite the differential.
Yeah something I've never really understood just listening to people.

I originally found a guy name desertsquirrel (or something similar). He was doing it outta a storage container. He was pretty good at documenting stuff and that's were my ideas started. 😉
 

Armdog

RDWC GROWER
Yeah something I've never really understood just listening to people.

I originally found a guy name desertsquirrel (or something similar). He was doing it outta a storage container. He was pretty good at documenting stuff and that's were my ideas started. 😉
I believe some are referring to TDS and Some are referring to EC. TDS is smaller number and EC is larger number. I was referring to TDS
 

Streetpro09

Tester
I believe some are referring to TDS and Some are referring to EC. TDS is smaller number and EC is larger number. I was referring to TDS
EC and TDS correlate, if I remember correctly. EC=electrical conductivity and TDS=total dissolved solids.

An EC of 1.0 = TDS of 500 on the .5 scale.

That's if I remember correctly. It's kinda late and I've smoked a few. 😉
 
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