PPM, PH, FLUCTUATE what mean?!
- Thread starter gvega187
- Start date
JediSmoker
Active Member
Drops - Plant is using more nutes than water
Raises - Using more water than nutes
Same - Equal water and nutes
Remember, ppm can "stay the same" but the plan is only using the nutes it needs, thus creating an "unbalanced" ppm
gvega187
Well-Known Member
I dont understand why you would not want the plants to be using an equal amount of water to nutes.
Could you please clarify for me how I can use these indicators to adjust my ppm and or add back fresh water. ? I believe I am confused on these matters.
thanks for reply
here is what I have found with my system. I have a 35g tub using a drip system of sorts. I run a 1/2" line along the table and have 1 1/8" line going to each plant. water drains back to res from table.
as for PPM. my PPM increases due to evaporation. every time the system feeds, the PPM goes up a little bit. when the PPMs get to my max I add water. as for PH rise. this is also normal. I was adjusting PH 2x per day to maintain 5.2-5.8 PH. I was told to let it rise to 6.5 before adjusting down to 5.2. the reason explained, was that the minor nutes are beter absorbed at 5.0-5.5, but the most important nutes like N,P and Mag were absorbed better at 6.5-7. so I am trying this to see how it goes. it maens I only have to adjust eod. I tend to keep mu PPM about 200PPM lower than desired, this allows for the increase durring the day with no need for adding water till nutes get to max level. hope this helps. just what I have observed. just a note in a flood and drain system I have used, while PH goes up, there is vey little evaporation so PPMs actualy drop due to use by plants.
as for PPM. my PPM increases due to evaporation. every time the system feeds, the PPM goes up a little bit. when the PPMs get to my max I add water. as for PH rise. this is also normal. I was adjusting PH 2x per day to maintain 5.2-5.8 PH. I was told to let it rise to 6.5 before adjusting down to 5.2. the reason explained, was that the minor nutes are beter absorbed at 5.0-5.5, but the most important nutes like N,P and Mag were absorbed better at 6.5-7. so I am trying this to see how it goes. it maens I only have to adjust eod. I tend to keep mu PPM about 200PPM lower than desired, this allows for the increase durring the day with no need for adding water till nutes get to max level. hope this helps. just what I have observed. just a note in a flood and drain system I have used, while PH goes up, there is vey little evaporation so PPMs actualy drop due to use by plants.
JediSmoker
Active Member
Lets say you have a 10 gallon tank. You then add nutes to make it 500PPM. After a week the PPM is 450 and there are only 8 gallons of water left. That means my plant has used about the same amount of water as nutes.
At this point your PPM is 450, but if you plant is in vegitation it has sucked alot of the nitrogen out of the nutes, therefore that 450 PPM is lacking in nitrogen, so adding nutes back into this 10 gallon tank is going to raise your PPM however still not have the nitrogen the plant needs. That is the reason for flushing every 2 weeks. Hope that helps explain that some.
If the plant is "thirsty" it will drink more water, and thus your PPM will RAISE. If your plant is not "thirsty" and is "hungry" it will use more nutes than water, thus lowering your PPM. It's almost impossible to tell you exactly what to do due to strains, envoirment, evaporation, etc ... you will just have to play with it to get it right. At times plants will use more nutes than water, and vice versa. All you can do is monitor your PPM and make sure to adjust as needed.
A good starting point for vegging plants is to keep PH from 5.7-6.1 and PPM from 400-800.
PPM goes up, Ph goes down=plants require less nutes.
PPM goes down, Ph goes up=Plants require more nutes
PPM stable, Ph goes up=Equilibrium=Good thing.
so flushing means to completley empty your resovoir and replace with fresh water and neuts again???
does this apply to every hydro/aeroponic system????
gvega187
Well-Known Member
thats what i was looking for chief. Thanks
JediSmoker
Active Member
Yes and yes, at least that is what I do. I flush them every 2 (sometimes 2 1/2 cause I am lazy) weeks.
NewGrowth
Well-Known Member
Here is simplified version:
1.Water level drops PPM goes up: Drop your nutrient strength in relationship to the PPM rise.
2. Water level drops PPM stays the same: You may be able to fine tune you nutrient strength, if growth is vigorous leave it alone.
3. Water level drops PPM drops: Raise your nutrient strength in relationship too PPM drop.
1.Water level drops PPM goes up: Drop your nutrient strength in relationship to the PPM rise.
2. Water level drops PPM stays the same: You may be able to fine tune you nutrient strength, if growth is vigorous leave it alone.
3. Water level drops PPM drops: Raise your nutrient strength in relationship too PPM drop.
gvega187
Well-Known Member
Ty for the response new G...it has been a lil while. Im going to start dropping in on your thread for small questions from now on.
A good summary of the concepts reviewed in this thread.
JediSmoker
Active Member
It would seem you are losing water faster than your plants are using the nutes. Your PPM is currently very low (to my standards) and if you add water it will lower your PPM evem more.
If your plants look healthy, I would just leave it alone and contiue to monitor it. In vegging stage I keep PH from 5.7-6.1 and PPM 400-600. I do whatever is nessassary to keep these readings on my meter. How often I need to make changes depends on how many plants I am growing and how fast they are growing.
I think this information is false. I cut my nutrients to 1.3 (Plants are 4-6 inches tall) and my PH stabalized. It was going from 5.7 to 8.3 everyday before I cut the nutrients
JediSmoker
Active Member
False? this statement has nothing to do with PH.
It's simply water/nute ratio. If you add water PPM will go down. If you take water out (usage, evaporate, etc) faster than the nutes get used PPM will go up. If the water loss = nute usage, PPM will stay the same. Its pretty simply really.
gvega187
Well-Known Member
lol the info is not false. Thats like saying that having to use nutrients is a myth or something...Its just part of hydro. Re-read the suggestions and try attacking your res again. Quite a ph swing you have there. Jedi, any ideas why his ph is whippin so hard?
I have had root problems swing ph #'s way down for a week or so.
I have had root problems swing ph #'s way down for a week or so.