Ph And Ppm: Expected Time For Fluctuation

[Trudope]

Hi All,

First grow here, learning lots while I grow in DWC. I have three plants going and they all look healthy, albeit short and bushy (although I am training them this way). I did however, expect my plants to be larger by week 3-4, so I'm constantly looking at where I can improve my grow. Here's what I've noticed from my data about pH and PPM.

I check my pH levels daily and generally pH down to 5.5 every other day. Within two days time, it raises back to 5.8-6.0. I check my PPM daily and it seems as if the plants either don't use them at all, or my PPM meter is junk. For example, I start with 550PPM after I clean the buckets. Within two days time, the PPMs will drop maybe 10PPM on average ( I have to take multiple readings because I get higher readings sometimes). So over a period of 1 week, I maybe lose 10-20 PPM at most. Do people experience higher levels of this generally? My plants seem healthy and are a solid green, so I don't think I have a nute lockout issue.

However, from what I'm reading is that if my pH is increasing, 5.5 -> 6.0, and PPM falling, I have too little nutes in the water?

How fast do your PPMs drop from the experienced growers?

 

[intheuc]

Hi All,

First grow here, learning lots while I grow in DWC. I have three plants going and they all look healthy, albeit short and bushy (although I am training them this way). I did however, expect my plants to be larger by week 3-4, so I'm constantly looking at where I can improve my grow. Here's what I've noticed from my data about pH and PPM.

I check my pH levels daily and generally pH down to 5.5 every other day. Within two days time, it raises back to 5.8-6.0. I check my PPM daily and it seems as if the plants either don't use them at all, or my PPM meter is junk. For example, I start with 550PPM after I clean the buckets. Within two days time, the PPMs will drop maybe 10PPM on average ( I have to take multiple readings because I get higher readings sometimes). So over a period of 1 week, I maybe lose 10-20 PPM at most. Do people experience higher levels of this generally? My plants seem healthy and are a solid green, so I don't think I have a nute lockout issue.

However, from what I'm reading is that if my pH is increasing, 5.5 -> 6.0, and PPM falling, I have too little nutes in the water?

How fast do your PPMs drop from the experienced growers?

In all the years I have been doing this, I have learned one key thing and that is to never chase the PH. As long as it's within 5.5-6.5, leave it alone.

Don't be so concerned with the meters that you fail to check the water levels. If the water level is dropping and the EC is rising, your remaining water is concentrated with nutes and you would add fresh RO water. This would cause a rise in EC.

If the water level is dropping and the EC is dropping then you top off your rez with nutrient solution to bring it back to your starting point.

I generally do the double up method... if I start at an EC of 1 and drop to .8, I top off my res to reach 1.2. This works for me but every strain and environment is different.

In a nutshell,

Base is 1.0

Next day, it's 1.4
The nutrients are too strong & one would add water to get back to 1.

However, if the next day it's at 0.6
The nutrients are too low & one would add nutrients to equal back to 1.

Make sure those water levels are dropping as EC drops & no one can tell you what they should be dropping by because growth patterns are different from plant to plant and environment to environment. Your plants are happy & healthy so they're telling you everything there is to know. Keep it simple.

 

[chemistry]

You can throw what you like at your plants, but they will only eat what they want to eat, and if they are green and healthy, then carry on doing what your doing until you see a sign that some thing is wrong.

 

[j wizzle]

In all the years I have been doing this, I have learned one key thing and that is to never chase the PH. As long as it's within 5.5-6.5, leave it alone.

Don't be so concerned with the meters that you fail to check the water levels. If the water level is dropping and the EC is rising, your remaining water is concentrated with nutes and you would add fresh RO water. This would cause a rise in EC.

Think you mean this will cause the EC to go down as you are now diluting the nute solution with water, just to clarify to the OP.



But to the OP,

This is how you can tell how much your plants are eating.

If you start off at 550 PPMs, and your plants drink water, your PH is going to go down normally, but your PPMs will not go down much as there is less water, so you now have a higher nute to water ratio. I wouldn't mess with you PH much, it will go up and down as you add water and nutes back in. Just let it do its thing, as long as it doesn't dip below 5.5 or spike higher than 6.5, you will be just fine. I don't even have to adjust my PH, my nutes bring it down perfectly with my RO water.

So if they drink 2 gallons of water, you add back 2 gallons of RO water.... now measure your PPMs. if they are at 400 PPMs, then your plants have eaten 150 PPMs of nutes, and you would need to add back 150 PPMs of nutes to get back on your feeding schedule. Make sure you allow the water to circulate for 30 mins or so, so it mixes really well before you measure your PPMs or you may get a bad reading.

over time, you will know how much your plants tend to drink/eat and you will be able to adjust your add back nutes pretty much on a regular schedule. Once you figure out how much you regularly add back, you can add a top off res with 20% nutes, etc.

I don't have a top off res, so I just add the nutes in when I add back RO water.