When to add nutes to E&F res.

[rj28racer]

Do I need to add nutes when I top off the res. with plain water to the desired PPM's ? Or do I go through a complete water exchange before adding more nute's ? Example- 10 gal res. start nutes.1200ppm's , plants use 1gal per watering 2 gal per day, when adding back the 1gal per watering do I add more nute's at this time, or do I wait until I have added back 10 gal to add nutes again. ?
Thanks tried to search no luck on clear answer.

 

[PoopyTeaBags]

i dont run ebb and flow but im sure its pretty standard to top off with plain water and change out your rez every 7-10 days.... some people dont ever change there rez and just add back but then you dont know what it has eaten and you may be adding back something that you dont need and not enough of somethign you do need....

 

[supersmallgiant]

I have been changing every 14 days with no top offs.

 

[rj28racer]

After 1 gallon fill back of plain distilled water, the ppm's drop an average of 150 ppm's per feeding. I take readings ppm , tdc initial , after feeding , after fill back with plain distilled water, then after making adjustments. Small 6 plant grow , small res. . Thanks for any help clearing this method up , trying to gear towards a little more automation, this is my first grow so I'm tracking everything and learning and hope to improve next cycle.

 

[Kcar]

Here's what I do with 2 40gal res. H&G nutes.

Wait till res is down 25% (10 gal for me)add the RO then I add 5ml per gal of A,B and CalMg
Then PH and measure PPM's again. It's usually pretty close.
After you've added back 50% of your capacity, it's time to change your res.
If your running additives you can give them 1/4 dose at the same time.

 

[kstampy]

Poopy is right you don't know what they're eating and you only know what you are putting in and there may or may not be too much or too little of X Y and Z nute with adding back. A lot will vary with plant:water amount it's pretty interesting. Top off with plain water for up to 2 weeks depending on how much love (nutes/$) you want to give your gals. Yes you can go a whole grow without adding nutes or you can even add back %s look up lucas formula around the web you'll see a lot of info on it. There's a lot of math involved so it is definitely not ideal for me to top off with %s of nutes since im usually baked while doing that...

 

[Medium Pimpin']

it all depends on what the res tells me as it lowers.
you have to let your plants tell you what your next move is.

ppm's go up/down as solution levels go down?
how's the ph move?

pretty much these 2 factors will tell you what the girls are eating.

i have gone with res changes weekly, and i've gone full cycles without a changeout.
all depends on them and how you feed em.

 

[rj28racer]

I am on first hydro grow. I chart PH readings and TDC readings at intial tank filled with distilled water and nutrieants to recommended PPM's, then feed, 10 to 12 hours after, just before next feeding I chart readings PH, TDC, I then fill tank back up with distilled water to the level marked inside the tank, I chart PH and TDC readings, if TDC is lower than intial readings before feeding, I add nutes back up to recommended PPM's and then adjust PH to 5.8, then feed again, repeat this every 12 hours. My question is , am I supposed to add nutes for every feeding like I have been, or do I wait until the amount of pure distilled water with no nutes put in after every feeding equals the total amount of the res, for instance a 10 gal res, plants use 2 gal water per day , 2 gal water per day is added back, do I only add nutes every five days ?

 

[Medium Pimpin']

it all depends on how the girls react.

say your water levels drop in the res (as they should)
starting point full is (random #'s) 5.5ph and 1000ppm.
say 3 gals leave the res, your readings have the ph going up and ppm coming down =too light of feed.
ph goes down and ppm's go up= too strong of feed.

you essentially want the levels to stay the same as res levels drop.
this means they are eating at a perfect mix.

say for arguements sake, you have too strong a feed, just top off the res and ph adjust.
too light a feed, add back as you refill the tank.

play with the #'s until you can keep em as steady as possible.
there is no real exact science on how to do this IMO.
let the ladies (and your meters) tell you what they want.

this will be a learning curve, but once you nail it, you'll never do anything but hydro!