Sounds good! Thanks man!
When to begin nutes in rdwc
- Thread starter 420Mn
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rkymtnman
Well-Known Member
my point was/is that giving it 1ppm if there is rot (and i think there is a mild case), it will be used up rapidly.
and yeah, flushing the whole pot is important. if you have some gunk near your stem, that's a good way to get rid of it.
I completely understand your point about the chlorine being used up faster if there is rot. I believe the same goes for dying organics, algae.
Flushing the pots absolutely makes sense! Just wanted to assure the process I was asking about was correct.
Thank you for the time you devoted to helping me today, man. I appreciate the valuable knowledge I've gained from it.
OldMedUser
Well-Known Member
You've dosed a bit more of the CalMag I assume? It could be septoria but I'm not positive and not really sure what to do about it if it is. I would spray some dilute silica product especially on the undersides of the leaves to see if that helped as it wouldn't hurt. When I was doing DWC I always added some Rhino Skin which is AN's version of potassium silicate to my nutes and never had spotting like that. The only place I ever had that was on a big outdoor plant 7years ago or so and it didn't seem to cause any real problems so I did nothing. I brought that one in to flower but it spent 2 weeks in the shop under a 400W while it got sprayed for mites and thrips before it went down to the grow room.
I'd consider it mild septoria and treat as such myself or ignore it and maybe it won't matter but that doesn't always work.
You've dosed a bit more of the CalMag I assume? It could be septoria but I'm not positive and not really sure what to do about it if it is. I would spray some dilute silica product especially on the undersides of the leaves to see if that helped as it wouldn't hurt. When I was doing DWC I always added some Rhino Skin which is AN's version of potassium silicate to my nutes and never had spotting like that. The only place I ever had that was on a big outdoor plant 7years ago or so and it didn't seem to cause any real problems so I did nothing. I brought that one in to flower but it spent 2 weeks in the shop under a 400W while it got sprayed for mites and thrips before it went down to the grow room.
I'd consider it mild septoria and treat as such myself or ignore it and maybe it won't matter but that doesn't always work.
You've dosed a bit more of the CalMag I assume? It could be septoria but I'm not positive and not really sure what to do about it if it is. I would spray some dilute silica product especially on the undersides of the leaves to see if that helped as it wouldn't hurt. When I was doing DWC I always added some Rhino Skin which is AN's version of potassium silicate to my nutes and never had spotting like that. The only place I ever had that was on a big outdoor plant 7years ago or so and it didn't seem to cause any real problems so I did nothing. I brought that one in to flower but it spent 2 weeks in the shop under a 400W while it got sprayed for mites and thrips before it went down to the grow room.
I'd consider it mild septoria and treat as such myself or ignore it and maybe it won't matter but that doesn't always work.
As for the calimagic, I think I'm still at 25%. A full dose of calimagic is over 400ppm. I followed the 120ppm that we discussed, which was advised by dropthatsound. But 25% was where I originally started when I first began using calimagic.You've dosed a bit more of the CalMag I assume? It could be septoria but I'm not positive and not really sure what to do about it if it is. I would spray some dilute silica product especially on the undersides of the leaves to see if that helped as it wouldn't hurt. When I was doing DWC I always added some Rhino Skin which is AN's version of potassium silicate to my nutes and never had spotting like that. The only place I ever had that was on a big outdoor plant 7years ago or so and it didn't seem to cause any real problems so I did nothing. I brought that one in to flower but it spent 2 weeks in the shop under a 400W while it got sprayed for mites and thrips before it went down to the grow room.
I'd consider it mild septoria and treat as such myself or ignore it and maybe it won't matter but that doesn't always work.
I will jump on Amazon and order some silica. Neem oil is an option thats discussed on septoria treatment pages.
The treatment for septoria is removal of infected leaves to stop it from spreading up the plant, remove any decaying matter, improving airflow. Supposedly that should eliminate it, but if it doesn't, then fungicide or neem oil is advised. Will silica provide the same benefits as neem or fungicide?You've dosed a bit more of the CalMag I assume? It could be septoria but I'm not positive and not really sure what to do about it if it is. I would spray some dilute silica product especially on the undersides of the leaves to see if that helped as it wouldn't hurt. When I was doing DWC I always added some Rhino Skin which is AN's version of potassium silicate to my nutes and never had spotting like that. The only place I ever had that was on a big outdoor plant 7years ago or so and it didn't seem to cause any real problems so I did nothing. I brought that one in to flower but it spent 2 weeks in the shop under a 400W while it got sprayed for mites and thrips before it went down to the grow room.
d improve airflow.
I'd consider it mild septoria and treat as such myself or ignore it and maybe it won't matter but that doesn't always work.
Billy the Mountain
Well-Known Member
You should really stick to EC when describing nutrient concentrations.
The max dose of CalMagic at 5ml/Gal provides 13ppm N, 81ppm Ca, and 25ppm Mg; so a max dose of CalMagic provides 119 ppm of nutrients, a far cry from 400ppm.
A TDS meter's ppm reading is only meaningful if you're measuring table salt.
OldMedUser
Well-Known Member
Silica will work against any fungal problem like powdery mildew etc and is a good supplement for overall plant health in hydro mostly as soil grows should have some natural silica in them. It is very alkaline and makes the leaves inhospitable to molds and fungi. Like bug sprays you want to do it with the lights and fans off so it stays wet longer.
If you removed all the infected leaves now it's not going to leave many for plant growth and would likely show again as the small, new leaves get bigger. You could strip all the big leaves off and they'll grow back tho. Your plants aren't really bushy so should have lots of air flow. I've used neem against bugs but for thrips and mites I find insecticidal soap with 10ml/L canola oil added works just fine. Need to make sure to use it before you have buds on plants tho the silica isn't going to ruin early buds.
OldMedUser
Well-Known Member
An EC pen measures the exact same thing but expresses the value in EC instead of ppm. They both measure conductive ions in solution from any mineral salt. Neither work for organic nutes worth a shit as organic matter isn't conductive.
Billy the Mountain
Well-Known Member
Precisely; all the more reason to stick to EC.
The bottom line is that the meter is measuring conductivity, not dissolved solids, so it's silly to pretend that it does.
It just causes needless confusion when referring to nute concentrations.
PPM ≠ PPM is a tough concept to grasp for some.
I will have to mix up a gallon of calmagic and test it, because I got 79ppm last time I added 1ml per gallon.
Yes, you have mentioned sticking with EC before. I appreciate the reminder. That was my intention, but I've been having conversations with another member and the discussions surround ppm, so it has me accustomed to referring to ppm. But, doesn't ppm and EC go hand in hand? One is a mathematical conversion of another?
Thanks, man! Silica it is. And the fan leaves are staying.Silica will work against any fungal problem like powdery mildew etc and is a good supplement for overall plant health in hydro mostly as soil grows should have some natural silica in them. It is very alkaline and makes the leaves inhospitable to molds and fungi. Like bug sprays you want to do it with the lights and fans off so it stays wet longer.
If you removed all the infected leaves now it's not going to leave many for plant growth and would likely show again as the small, new leaves get bigger. You could strip all the big leaves off and they'll grow back tho. Your plants aren't really bushy so should have lots of air flow. I've used neem against bugs but for thrips and mites I find insecticidal soap with 10ml/L canola oil added works just fine. Need to make sure to use it before you have buds on plants tho the silica isn't going to ruin early buds.
Are these a good choice for silica, or is there a different product you would suggest? I'm leaning towards the second on as it's purely silica.Silica will work against any fungal problem like powdery mildew etc and is a good supplement for overall plant health in hydro mostly as soil grows should have some natural silica in them. It is very alkaline and makes the leaves inhospitable to molds and fungi. Like bug sprays you want to do it with the lights and fans off so it stays wet longer.
If you removed all the infected leaves now it's not going to leave many for plant growth and would likely show again as the small, new leaves get bigger. You could strip all the big leaves off and they'll grow back tho. Your plants aren't really bushy so should have lots of air flow. I've used neem against bugs but for thrips and mites I find insecticidal soap with 10ml/L canola oil added works just fine. Need to make sure to use it before you have buds on plants tho the silica isn't going to ruin early buds.
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Billy the Mountain
Well-Known Member
Yes, the ppm displayed by a TDS meter is simply EC * constant. The problem is that the unit, "PPM" does not represent the ppm in solution unless you happen to be measuring sodium chloride with a 0.5 conversion meter, or potassium chloride if you're using a .7 conversion meter.
It's just ridiculous to be referring to hydroponic solutions in terms of ppm values taken from an EC/TDS meter. The ppm values are meaningless or worse.
OldMedUser
Well-Known Member
Much easier to grasp than pH which is much more intricate than EC/ppm.
Both EC and TDS pens measure the exact same thing but express it using different units. Like the speedometer in my car. It has two sets of scales in kph and mph and gives me two different numbers but measures the same thing. The distance covered in a certain amount of time. We have an old wall thermometer that does the same thing but in °F and °C. -40 is the only place where they match up and that's friggin cold in either scale as we get a little of that each winter here. Not for long tho most years where our average winter temp is a balmy -20C. I managed to load my water truck on a job once when it was -51C but none of the seismic drilling trucks could get a drill spinning so we all went back to camp for two days until it warmed up to -40. I still got my 12 hours/day pay tho we usually worked 15 or more every day so no overtime.
Both pens measure the electrical conductivity of a given solution but have different ways of expressing their values. Some pens have a button you can press to see both readings if you prefer one over the other. I've always used ppm so am more familiar with that tho it takes me but a second to look at my conversion sheet to know what someone is talking about if they tell me readings in EC. I grew up using the imperial, (Canadian), system but when I went back to school in my 30s to get a diploma in environmental chemistry I had to learn how to use metric so now I'm fairly fluent in both systems. I still use feet and inches etc when working with structural things but but greatly prefer metric for liquid and volume measure. The base 10 math is much easier to work with than fractions tho I'm often converting those in my head as I have a greater feel for the old ways in things. Like when I catch a fish I'm not thinking that one's about half a kilo, I'm thinking that's a good pound right there.
I printed this out so I have it at hand. My first pen I bought in '82 and still use is a Hanna that measures at 10x. I got a new one 7 or 8 years ago that measures in single digits and calibrate that one at 20ppm so I can use it when I'm making colloidal silver.
OldMedUser
Well-Known Member
Any will work. I have some basic stuff that is 4x the concentration of the AN Rhino Skin but the Rhino is made to work with the pH Perfect nutes so is buffered and doesn't raise the pH as high as plain stuff which will raise it to 10+pH. For the same amount Rhino goes about 8.5 if I'm remembering correctly. 5 - 10ml/L/qt should be good for a foliar spray but there may be instructions on the bottle so go with that if it has it. You just want to raise the pH of the leaf surface so it can't spread or even grow. Fungicides are meant to kill it where the silica just alters it's environment so it can't live there any more.
OldMedUser
Well-Known Member
You really have it all wrong as I explained above before reading this one.
Check out this video if you don't believe me.
Thank you for explaining what the silica and fungicides do! It's interesting to know that the silica raises the ph of the leaves to create an uninhabitable environment. Knowing the actual purpose of applying it is very beneficial. I understand it strengthens stems and increases growth and yield while helping the plant be more resilient to heat/cold stress etc. Sounds like it has many beneficial properties.Any will work. I have some basic stuff that is 4x the concentration of the AN Rhino Skin but the Rhino is made to work with the pH Perfect nutes so is buffered and doesn't raise the pH as high as plain stuff which will raise it to 10+pH. For the same amount Rhino goes about 8.5 if I'm remembering correctly. 5 - 10ml/L/qt should be good for a foliar spray but there may be instructions on the bottle so go with that if it has it. You just want to raise the pH of the leaf surface so it can't spread or even grow. Fungicides are meant to kill it where the silica just alters it's environment so it can't live there any more.
I ordered the second one just before you responded.
Thanks again!
Billy the Mountain
Well-Known Member
What did you consider to be "all wrong"?
The meter measures conductivity (current to be precise). The ppm values displayed are derived values, not measured.
The two most common scales are based on specific salts:
1EC of NaCl corresponds to 500ppm (0.5 scale)
1EC of KCL corresponds to 700ppm (0.7 scale)
For anything else, the ppm readings are misleading as they don't actually represent the elemental ppm in solution.
It's not a difficult concept.
OldMedUser
Well-Known Member
I didn't see the 2nd one the first time but that's the one I'd recommend to get. Half the amount and I assume cheaper as well. A little goes a long way but if you use it in your nutes make sure to add it to your water first then adjust the pH down to around 7 before adding nutes to it. The nutes will pull the pH down some so might end up where you want to be after that. Let me know how it goes and what pH you get when mixed for the nute tank if you do that. Like most everything I would only use half the recommended dose. A lot say to only use it in flower but it's good for the plants from early veg on. Feeding them some would likely support the foliar spray efforts so might be a good idea too. For that I'd figure out the half dose then add that to water for your top-up, adjust pH to about 6 or less then add it by itself to the tank slowly. Check the ppm before adding then after it's circulated for a while so you can take that into account when figuring out how much nutes you need to bump up or maintain your ppm level. Don't count it as your actual nute level like with the CalMag.
Hope you're keeping track of things like that so you can make alterations as you go along.