Grow Mediums PickleRicks first DWC - LED

[Mañ'O'Green]

I have moved away from DWC to rockwool cubes with a drip system. I made this move for two reasons; first it is so damn hot here controlling the heat in the reservoirs is expensive and second I save about 70% to 80% on nutrient use. That said; I have had many successful DWC grows. RDWC was a pita trying to keep roots out of the plumbing. From the day the seedling's roots reached the water I ran nutrients @ 50% of manufactures chart strength ~ 600 PPMs. Botanicare HydroGuard saved my crop once when I got root rot and became a staple in ALL of my DWC grows. Never a problem after that even with reservoir temps in the mid 80°Fs - You should be using it. It is way better to use a good manufacturer's entire cannabis nutrient system - they know more than we do about their products and they are made to work together. Just pick one there are many good ones out there. I learned this the hard way! It is all about the balance. It is called Liebig's law of the minimum this web page is a simple explanation but it explains why adding a single nutrient may not address a deficiency. This is also the reason why you need to change the nutrients in the reservoir every week. There is just no way without a lab to know what the plants have been using and this will restore the critical balance. I used a top off tank with a nutrient mix of about 30% of what was in the res between weekly changes. This keeps the PPMs pretty close to the starting strength. I had it connected to a float valve that maintained the res level at all times.

You do not push your plants growth into flower with nutrients (you can with your light schedule on photoperiod plants) instead you follow the plant with the nutrients based on the plants growth stage. The first two weeks of actual flower is still veg nutrients in the res. Then start your bloom nutrient regime. At this point up the PPMs to ~850, do a 3 to 5 day flush when done, dry, cure and enjoy.

 

[PickleRick]

Hey Rick thought I pull up a chair and see if I could lend a hand - not that I'm an expert by any means. I am only on my second hydro grow but I have been growing in soil for a couple of years. On my first hydro grow I had a problem like yours. I do not add cal/mag until I get to week 4. Around week 5-6 I started to see leaves that looked like yours. I figured that it was w cal/mag def so I upped the dose. The problem did not improve, so I upped the dose again but the problem seemed to be getting worse. After a bunch of research I began to think that I actually had a P def, so I began to try to increase the P. Nothing helped. A few weeks after I had harvested I ran across something that @Muddy said about going lite on the cal/mag supplements as too much cal looks just like a P def.


Muddy said "Add enough to your base water to bring the starting ppm to between 125 - 150, then add your nutes. My RO is 12 ppm and 3 ml per gallon gets me to 125. Too much calcium can be an issue as well. It can lock out the nutrients and you'll start getting what looks like a P deficiency. What I run into in rdwc is the occasional strain related magnesium deficiency. Some just need more than others. I treat those with epsom salts rather than adding more cal/mag."

Hope this helps and you get it sorted out. Forgot to mention - nice thread, very informative.

Hey man, thanks for dropping by!
I'm very unsure as to what it actually is. That is around what I have now in the latest ress change. The 8ml more of cal/mag brought my RO water to 140ppm (around there).
I'm doubting that it is P deficiancy, since it started in week 2 already and they were both on bloom nutrients, since I hadn't been able to get grow nutrients.
Also I don't think it is a look out since I've been feeding them so little.

Right now I think they both lock a bit perkier, but I'm staring myself blind every day so...

Thanks for the input. Will keep updating how it moves along.

 

[PickleRick]

I have moved away from DWC to rockwool cubes with a drip system. I made this move for two reasons; first it is so damn hot here controlling the heat in the reservoirs is expensive and second I save about 70% to 80% on nutrient use. That said; I have had many successful DWC grows. RDWC was a pita trying to keep roots out of the plumbing. From the day the seedling's roots reached the water I ran nutrients @ 50% of manufactures chart strength ~ 600 PPMs. Botanicare HydroGuard saved my crop once when I got root rot and became a staple in ALL of my DWC grows. Never a problem after that even with reservoir temps in the mid 80°Fs - You should be using it. It is way better to use a good manufacturer's entire cannabis nutrient system - they know more than we do about their products and they are made to work together. Just pick one there are many good ones out there. I learned this the hard way! It is all about the balance. It is called Liebig's law of the minimum this web page is a simple explanation but it explains why adding a single nutrient may not address a deficiency. This is also the reason why you need to change the nutrients in the reservoir every week. There is just no way without a lab to know what the plants have been using and this will restore the critical balance. I used a top off tank with a nutrient mix of about 30% of what was in the res between weekly changes. This keeps the PPMs pretty close to the starting strength. I had it connected to a float valve that maintained the res level at all times.

You do not push your plants growth into flower with nutrients (you can with your light schedule on photoperiod plants) instead you follow the plant with the nutrients based on the plants growth stage. The first two weeks of actual flower is still veg nutrients in the res. Then start your bloom nutrient regime. At this point up the PPMs to ~850, do a 3 to 5 day flush when done, dry, cure and enjoy.

Hey mate, thanks for the input!

I can't get hydroguard where I live, using SM-90 from Nutrilife. Got the impression that it was a good substitute for hydroguard, am I mistaken? I was expecting high temps, both since I started in summer and I have a small grow area.
I also change the water in both buckets every week religiously, with RO water.

Time will tell how it goes, do stick around and tell me if I mess stuff up! :smoking:

 

[PickleRick]

Looking neeat man, wish you luck on your first auto grow ! What did they say at the infirmary, what seems to be the problem?

Thanks dude!
A few tips, heres the LINK, if you wanna check it out.

 

[PickleRick]

Looking real good. Where did you pick up that little white plastic piece to turn the branch for lst?

Thanks man!
They are called "bendz", not sure if they are avalible on ebay or such. But like I said ain't gonna use them, they seem to be more for super-cropping then lst.

 

[Mañ'O'Green]

Hey mate, thanks for the input!

I can't get hydroguard where I live, using SM-90 from Nutrilife. Got the impression that it was a good substitute for hydroguard, am I mistaken? I was expecting high temps, both since I started in summer and I have a small grow area.
I also change the water in both buckets every week religiously, with RO water.

Time will tell how it goes, do stick around and tell me if I mess stuff up! :smoking:

Rick:

I have not used SM-90 since I hit on HydroGuard many years ago and was so successful with it; I just stuck with it. They changed the formula a couple of years ago and I was really worried because I depended on it. All is well with the new formula.

I am lucky to have good tap water at ~ 140 PPMs so I do not need RO. Are you adding something like House & Garden's PH Osmosis/Stabilizer to buffer your PH?

 

[woody]

Sm90 has saved my ass in dwc a couple times- works great for me

 

[Journey Man]

I will use SM-90 aswell, as i cant get the hydroguard. If i do okey, i can guarantee it works.

 

[Duckster]

I was digging in my nute bin this morning and found a brand new unopened bottle of SM-90. I must have bought it after my last grow. But fecked if I can recall what I'm supposed to do with it. I need a bit of enlightenment lads.

 

[woody]

I was digging in my nute bin this morning and found a brand new unopened bottle of SM-90. I must have bought it after my last grow. But fecked if I can recall what I'm supposed to do with it. I need a bit of enlightenment lads.

Sm90 is great stuff duck! It keeps your res clean and sterile- preventing plythium and other root nasties from forming.
I wouldnt try a dwc grow without it- makes growing without a res chiller a lot easier.
I use it at .5ml per litre