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Advanced PH/TDS question

flogger11

New Member
Hey guys I am running a drip system with a fogger and airstone in the res and I have a question.

I know a person needs to know their baseline TDS when adding nutes, my question is when I use my PH up it appears to be raising my total dissolved solids. I did a control test, just used some water in a glass, I raised the PH with my PH up and sure enough, it raised my TDS. Does this mean everytime I use PH up I have to raise my baseline reading for my TDS? If this is the case I am well over 1000 as a baseline, yikes!

I am using Moondust all in one nutes while using a PH up powder. Is there any PH up that will not affect my TDS reading? Thanks for the hand everybody!
 

hemivette

New Member
You shouldnt have to add enough PH up to make too much of a difference. In fact the only time you should have to add it, is in your initial mix. After that the plants should keep it up if they are feeding properly.

I always Mix my nutes first, then fill my res, and then adjust the PH to 5.5ish and let it climb on its own (from feeding) to 6.4. Thats usually half way through the week, I top off the res and knock it back down to 5.5. By the end of the week its back up to 6.2, and we start again.

Be careful adding too much PH up/down, or you could get nute lockout. Hope this helps. h
 

flogger11

New Member
You shouldnt have to add enough PH up to make too much of a difference. In fact the only time you should have to add it, is in your initial mix. After that the plants should keep it up if they are feeding properly.

I always Mix my nutes first, then fill my res, and then adjust the PH to 5.5ish and let it climb on its own (from feeding) to 6.4. Thats usually half way through the week, I top off the res and knock it back down to 5.5. By the end of the week its back up to 6.2, and we start again.

Be careful adding too much PH up/down, or you could get nute lockout. Hope this helps. h
So what does it mean if a person is adding PH up on a daily and sometimes twice daily basis? Not everyday, but probably every other on the average. The res water temp was at 80F and now its down to 75, think that it would help if I could get the water temp down to 70 or would it be something else... thanks for the hand!
 

hemivette

New Member
What Ph is your water your using? Most tap and store water starts at 7.0. My nutes usually drop it a point. What are your Ec's?

Temps can have a major affect, I dont let them get above 70. I have 2 two ltr bottles full of water and during the summer, I keep 1 in the res and 1 in the freezer. Works well. h
 

flogger11

New Member
What Ph is your water your using? Most tap and store water starts at 7.0. My nutes usually drop it a point. What are your Ec's?

Temps can have a major affect, I dont let them get above 70. I have 2 two ltr bottles full of water and during the summer, I keep 1 in the res and 1 in the freezer. Works well. h

Water PH 6, Temp was at 80 for eight weeks, now at 75, will get it down to 70. I suppose I probably have rot setting in. So is it hygrozyme and a chiller time?
 

SteveHman

Member of the Month: Aug 2011 - Nug of the Month: Oct 2011
Water PH 6, Temp was at 80 for eight weeks, now at 75, will get it down to 70. I suppose I probably have rot setting in. So is it hygrozyme and a chiller time?
Definitely one or both. Do you have your fogger on a timer? If possible place it in a separate container/res adn pump the fog into the chamber. Those foggers will raise the temp of your res if you run them 24/7. I started off with them and stopped using them after my first grow. I keep my res in the 65 range. 80 is inviting root rot and a host of other things, the higher the temp the less O2 the nutes can hold.

You shouldn't need to adjust you pH, and twice a day is an indication something bad is going on. What is the size of your res? How often do you change nutes? How often do you calibrate your pH pen? is the plant showing any signs of nute lockout? What media are you using?

I would remove the fogger, flush out the system, adjust the pH of your water and then add the nutes. See how it goes from there.
 

hemivette

New Member
I keep my res in the 65 range. 80 is inviting root rot and a host of other things, the higher the temp the less O2 the nutes can hold.

You shouldn't need to adjust you pH, and twice a day is an indication something bad is going on.

adjust the pH of your water and then add the nutes. See how it goes from there.
I always do the PH after the nutes, cause my nutes affect my Ph up to a whole point. And ya I would get some kind of cooler in there. I keep mine between 65-70. Like Steve said, "the cooler it is, the more oxygen the water can hold". h
 

flogger11

New Member
Definitely one or both. Do you have your fogger on a timer? If possible place it in a separate container/res adn pump the fog into the chamber. Those foggers will raise the temp of your res if you run them 24/7. I started off with them and stopped using them after my first grow. I keep my res in the 65 range. 80 is inviting root rot and a host of other things, the higher the temp the less O2 the nutes can hold.

You shouldn't need to adjust you pH, and twice a day is an indication something bad is going on. What is the size of your res? How often do you change nutes? How often do you calibrate your pH pen? is the plant showing any signs of nute lockout? What media are you using?

I would remove the fogger, flush out the system, adjust the pH of your water and then add the nutes. See how it goes from there.
Rez is 18 gallon tote, 10 gallons of water. Changing water/nutes every two weeks. Just using a basic PH liquid tester, cheap and accurate, I think. Ya, nute lockout for sure. Organic plug inside hydro corrals inside 3" net pots, sitting in top of 18 gallon tote, drip feed system (plus kinda DWC, roots are1/2 submerged).

I pulled the fogger, guess what? Res went from 75 to 69 in less than 20 minutes, thank god!!! Changed my water, added 6ml per gallon of Hygrozyme and went with GH Bloom, the solid type, I sure hope this all leads to healthy plants. Thanks for the great advice my friend! :thumb:

Am I giving up anything by dumping the fogger or was I just being redundent?(I already have a drip system going, one drop per second 24/7).

On a young plant do the roots get their nutes from the drip since they havent reached the water in the res yet?


Thanks again for the hand everybody!
 

hemivette

New Member
Its a good Idea to have an airstone in the res, (if you dont) especially if roots are in it. Also this may be one of your problems, 2 weeks is too long between res changes. I was doing 10 days, now I do 7, and they are a lot healthier than previous grows. h
 

AireDog

New Member
I am using Moondust all in one nutes while using a PH up powder. Is there any PH up that will not affect my TDS reading? Thanks for the hand everybody!
TDS (total dissolved solids) is a value based on EC (electrical conductivity). Hydroponic pH UP is usually potassium based, a mineral salt, so it increases the conductivity of your solution. Using other substances, not specific to gardening, to adjust pH, can lead to other problems, such as nute lock-out or burnt plants.

So what does it mean if a person is adding PH up on a daily and sometimes twice daily basis?
Is your TDS rising while pH falls? If so, your plants are drinking more water than taking up nutes. Rough rule of thumb:

TDS up, pH down
Nutrient solution is too strong.​

TDS down, pH up
Nutrient solution is too weak.​

TDS and pH stable, while volume of solution drops
Equilibrium, and that is the ideal.​
 

flogger11

New Member
Its a good Idea to have an airstone in the res, (if you dont) especially if roots are in it. Also this may be one of your problems, 2 weeks is too long between res changes. I was doing 10 days, now I do 7, and they are a lot healthier than previous grows. h
I do have an airstone, it doesnt appear to be doing much, just a small stream of bubbles from one end. Is this enough or should I find a diff stone? Thanks again for the hand!

PS Three hours after fogger removal res is down to 68!! :)
 

SteveHman

Member of the Month: Aug 2011 - Nug of the Month: Oct 2011
You can't over-aerate your res. I have a massive micro-pore airstone (about $40) and a big airpump that is dedicated to it. It creates a lot of movement in the res and splashes nutes all over the res cover. A setup like that would be a good option for your DWC, it would create a constant mist of nutes to the root zone, keep the nutes agitated and mixed and provide a ton of O2 to the nutes in the res.

More air = more better!
 

AireDog

New Member
If you can, check your roots. They should be crisp and color should be white or beige, texture should definitely not be slimy; smell should be clean and cucumber like. If they smell sour or swampy and there are dark squishy or slimy sections; you have rot. Use a weak nutrient solution with H2O2 and hygrozyme. Here's a shot of some of my roots, you can see a bit of the aeration as well:



Here's my res, with a micro-pore air diffuser; the second pump feeds a chiller:



Definitely keep root zone below 70F and aerate. Personally, I have 10L/bucket. FWIW, after about the 5th week of flower I have dropping pH issues as well. This seems to be an issue in DWC type systems and causes are varied.
 
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