Ro water question.

Fawkes420

Fawkes420

Well-Known Member
Just bought a RO filter, now i wonder a little how to measure nutes.

I have today a total ec of .85 with a background ec of .4.
With ro water,,, should i go for .85, or lower since there is no background ec (get .01 after filtration)?
Thinking .85 might be a little too hot?

For now i added Epsom salt 1g/gallon (EC.3) and then nutes up to .85

The reason i wonder is that now plant is drinking but ec and ph is slowly rising.
 
OldMedUser

OldMedUser

Well-Known Member
Fawkes420 said:
Just bought a RO filter, now i wonder a little how to measure nutes.

I have today a total ec of .85 with a background ec of .4.
With ro water,,, should i go for .85, or lower since there is no background ec (get .01 after filtration)?
Thinking .85 might be a little too hot?

For now i added Epsom salt 1g/gallon (EC.3) and then nutes up to .85

The reason i wonder is that now plant is drinking but ec and ph is slowly rising.
Click to expand...
If you are getting 0.4EC out of your RO unit then something isn't right. That's 200ppm, (Hanna scale), when it should be near zero. I buy my RO in town and check each new batch when I get it home and the last ones were 4ppm.

I start my clones in DWC at 300ppm/.6EC so fro you to be at 225ppm at the end of the first week of flowering is way too low. I'm usually in the range of 800 - 1000ppm but may be a bit lower if my RH is really low.

During the stretch the plants eat more than at any other time and that's when they set their bud sites and need extra flowering nutes too.

I've heard of people running at 300ppm for the whole grow but that was years ago and most are running around 1000 or higher.

Are you seeing any bud sites yet?

I have this printed out for quick translation between EC and the various ppm types.

PPM-EC-CF8x11.jpg
 
Fawkes420

Fawkes420

Well-Known Member
OldMedUser said:
If you are getting 0.4EC out of your RO unit then something isn't right. That's 200ppm, (Hanna scale), when it should be near zero. I buy my RO in town and check each new batch when I get it home and the last ones were 4ppm.

I start my clones in DWC at 300ppm/.6EC so fro you to be at 225ppm at the end of the first week of flowering is way too low. I'm usually in the range of 800 - 1000ppm but may be a bit lower if my RH is really low.

During the stretch the plants eat more than at any other time and that's when they set their bud sites and need extra flowering nutes too.

I've heard of people running at 300ppm for the whole grow but that was years ago and most are running around 1000 or higher.

Are you seeing any bud sites yet?

I have this printed out for quick translation between EC and the various ppm types.

View attachment 4278178
Click to expand...
Hi.
May be i was mixing things up in first post....
I had .4 background before i use RO filter, now i have ec .01.
Will post pic tomorrow, dark hours now.

How du i calculate/dosing epsom salt? Is that to be addad to total nutrients?
This is my first try with DWC and i have had problems dialing in nutes all the way.
It seems like i just can't get it in my head, lol.
 
rkymtnman

rkymtnman

Well-Known Member
what nutes are you using?

epsom is 1 gram/gallon like you are using. that will keep any Mg deficiency away

keep an eye out for Calcium deficiency with RO water too. look like brown rust spots.
 
Fawkes420

Fawkes420

Well-Known Member
I use Plant Magic DWC http://www.plant-magic.co.uk/products/dwc/38/

I really can't get it into my head. When i used tap water i had ec .85. That's around 425ppm. If i tried to raise ec i had to lower ec as according to this file when water is falling and ec/ph is rising, which it does in my case, i should lower ec (5th and 6th line from bottom).

I mean,,,,, if i lower much more it would be plain water, lol, definitely no way near 800-1000 ppm range.Water_ec_ph.jpeg
 
rkymtnman

rkymtnman

Well-Known Member
sounds like you might have some root rot going on. are you sure they are fine? not brown, slimy etc.
 
Fawkes420

Fawkes420

Well-Known Member
I use H2o2 and enzymes from plant magic, the roots are tanned ( think the enzymes is to blame since it is a brown liquid). No smell or slime. No light leak,black bucket. Good airflow. Temp below 21C. Smells kind of fresh to be honest. But as i said,,, they looks like shit, haha.
I have had root rot in mind, guess yuo might be right there.
 
rkymtnman

rkymtnman

Well-Known Member
you can try this and see if this gets them eating again:

give them a 6 hr flush with just RO when lights come on , dump that water out and then start feeding again at that 0.45 that i mentioned earlier. i would almost bet they will start eating.
 
OldMedUser

OldMedUser

Well-Known Member
Fawkes420 said:
Hi.
May be i was mixing things up in first post....
I had .4 background before i use RO filter, now i have ec .01.
Will post pic tomorrow, dark hours now.

How du i calculate/dosing epsom salt? Is that to be addad to total nutrients?
This is my first try with DWC and i have had problems dialing in nutes all the way.
It seems like i just can't get it in my head, lol.
Click to expand...
That's a lot better then. 5ppm is fine.

I often go a whole grow without ever changing nutes. I just check ppm and add small amounts of nutes to keep the ppm where I want it as the plants bring it down. I've done about 50 DWC grows since '01 so I've had a bit of practice tho.

I'll add a tbsp of epsom salts but just once for a tub of nutes that's 35 - 50L depending on if it's the short or tall Rubbermaid tub. If it's a while between nute changes then I'll toss in a bit more now and then but really don't keep track. With CalMag it's much the same but never more than 1/4 - 1/2 of the recommended doses. I use AN pH Perfect nutes and they have quite a bit of both Ca and Mg.

The old AN nutes weren't pH perfect so when I checked pH I'd add conc sulfuric acid to bring it down to 5.4 or so and in the 3 days between top ups it would creep up to around 6.3. I would top up with RO water first, let it sit for 30 min or so then check pH and ppm and adjust as needed. Was so regular I'd only check every few top ups. Would just add 5 drops of acid and a squirt of all 3 nutes. Lazy and complaisant is me. :)

I also used to add 0.5ml/L of 35% food grade peroxide twice a week to prevent root rot until I built a chiller out of an old water cooler then stopped the peroxide with never a sign of root rot. Only ever had rot twice and both times I started the cuttings in a mix containing real dirtand think the rot came from that. Didn't have a chiller for the first 30 grows or so and it happened to two of those. Heavy doses of peroxide beat it back and I never lost more than a plant or two out of the dozen or so that might be in one tub. I grew forests in those tubs. lol

JungleGrow.jpg
 
Fawkes420

Fawkes420

Well-Known Member
rkymtnman said:
you can try this and see if this gets them eating again:

give them a 6 hr flush with just RO when lights come on , dump that water out and then start feeding again at that 0.45 that i mentioned earlier. i would almost bet they will start eating.
Click to expand...
Is that with epsom included? 1 gram / gallon is about ec .1, that would leave me with about .3 epsom and .15 nutes if that's the case.
 
OldMedUser

OldMedUser

Well-Known Member
I wouldn't be too quick to soak in RO water only unless you are sure you have root rot. I never changed my nutes at all when I had it and suddenly going to zero ppm can have bad results. I'd pour some of the water with peroxide in it thru the net pots and would use up to 5ml/L of the 35% daily to win those wars.

If you have rot it's pretty easy to tell. Chunks of roots will fall off and usually be drifting around in the pail. There will be slime and usually it'll stink.
 
rkymtnman

rkymtnman

Well-Known Member
i would leave out the epsom for now. let's get them eating again and then you can always add it a few days later. or you can even foliar feed the epsom which they actually use faster than thru the roots
 
rkymtnman

rkymtnman

Well-Known Member
OldMedUser said:
I wouldn't be too quick to soak in RO water
Click to expand...
i suggested that because the plants don't appear to be eating at the moment. and from what he described, i don't think there is rot.

i think a quick flush is a good way to give them a refresh and start eating again
 
Fawkes420

Fawkes420

Well-Known Member
Well, i think it might be rot, although i used h2o2 and enzymes.
I got some roots floating around and i can pretty easy tear down roots from the root ball.
The strongest peroxide i can get my hands on is 12%. Should be ok to use 15ml/l (3x5ml) to get me around the same concentration,,, right?

But,,,, i'll do nothing before i post some pics and then i get the judgement ;)

The day when i dust off my autopots is coming closer :)
 
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