[Happiness]

Need to know if the PPM is supposed to change as the plants use it.

How much should change for each period? Seedling, veg, bloom.

What does up or down indicate?

I am using am ebb and grow system, GH nutrients, following their easiest progam.

Thanks all!!!

[sneaky101]

Sure it will change. As the water level lowers that will also effect the ppm. Depends on alot of things as how much it changes. I top off my rez every 2-3 days and the girls (2) use about 1 gallon/day between the 2 of them and the meter usually reads 100-200 ppms lower than when the last nutes were added. I add and replenish nutes every few days myself. Just keep it in the range you want after each top off and check the ph too.

[Happiness]

I check and adjust my nutrient levels once, sometimes twice a day. The ph is always between 5.8-6.2.

I have 16 growing that are 18 days old today.

[FreezerBoy]

Originally Posted by sneaky101

As the water level lowers that will also effect the ppm.

That comes from over or under feeding.

Because nutes are acidic EC and pH move in opposite directions. EC up, pH down is too rich. EC down pH up is too lean.

[Happiness]

Originally Posted by FreezerBoy

That comes from over or under feeding.

Because nutes are acidic EC and pH move in opposite directions. EC up, pH down is too rich. EC down pH up is too lean.

So should it change in a specific direction?

[FreezerBoy]

I found EC flat, pH flat led to deficiencies after a few weeks. But, I only maintain the tank twice a month. No one pH level allows proper absorption of all nutes so a small swing is good for you. 5.6-6.0.

Which way is best is up to you. I'm a Ronco style grower. I like to set it and forget it. I barely overfeed at pH 6.0. Over two weeks EC climbs 0.1-0.2, pH drops to 5.6 and straight tap water returns me to my original numbers.

These are your babies, you want what's best for them but, these plants are incredibly adaptable and resilient. Don't stress out, this is supposed to be fun. Whatever your nute bottles list as a feeding regimen, cut it in half and see how plants react. While many have success with Lucas' 0-8-16 formula, I've had plants say 0-3-6 is too strong. Rather than use EC and pH to match a chart, use it to speak directly to your plants.

[Happiness]

What's the best way to tell when its too much?

[FreezerBoy]

see post 4