Add Back Vs Top Off Method - DWC

[The Germinator]

I've been topping the res off daily with water. No nutes. My bucket has 4 gallons water. I've read when you've added back the amount of your bucket that you should change the bucket. That would be every 3 days for me. She's drinking like crazy.
Question is. If I use the add back method where u add back nutes everyday how do I know the amount of nutes? Just make another four gal bucket with my original formula and dip from that bucket to fill up?
What do you dwc people do? Thank You.

 

[Scientific]

> Question is. If I use the add back method where u add back nutes everyday how do I know the amount of nutes? Just make another four gal bucket with my original formula and dip from that bucket to fill up?

That's what I did and it worked fine. Then I changed the media completely every Saturday morning, switching to the next week's nute ratio in Nebula Haze's diluted General Hydroponics regimen.

But all along in the back of my mind I heard the voice of the water top-off guys saying you just add H2O and to do otherwise was dumb.

My theory was that I was using quite dilute nutes (~400 PPM--the most my Dwarf Low Flier would tolerate) so I'd just always keep it at that max level.

When I was researching Lucas Formula recently, Lucas himself advocated just giving the plants what seemed to me a whopping big dose and then successively top of with just water as you said until the amount added equaled the res volume. I think if I had done that I would have burned the plant at the beginning, or if I had started with more dilute nutes, have over-diluted by the time I was done.

I don't have the answer, but it does seem to me that keeping the plant constantly fed with the most concentrated solution it can handle is ideal.

 

[The Germinator]

Yes I think keeping the plant fed with the most concentrated solution it can handle would be ideal too. Seems like common sense to me. But. Having said that I wonder if it could cause greater salt buildup, possibly even lockout.

 

[The Germinator]

Well I've been adding back full strength nute water daily. It's working great so far. Doing a bucket change tomorrow to keep the nutes balanced.

 

[MrMedic]

I need to add about 4 gallons a day to my res. What I do is have 2 buckets of r/o wanter and add my nutes and additives to the one and try to get close to the desired ppms or slightly above. Then I wound top with either bucket depending on what my res is doing. If the ppms have climbed, I would then just top up with plain r/o until you reach what you want your nutrient strength to be. If the ppms lowered I would add the nutrient water to reach 50 ppms above what ot was previously at.
If your ppms are rising, you're feeding too heavy. If its lowering you're feeding too weak. Finding this balance point will also make your ph quite stable. This is my understanding of add back.
Cheers!