RDWC Nutrient Change Question

I have a 5 bucket 13 GAL rdwc system in 3rd week of Veg ; I have added Scrog net and will no longer be able to lift up the plants to remove the extra water with a shop vac. I would appreciate if someone could clarify the following :

When changing out the nutrients , after draining from the bottom of the system , I am left with about 1/2 gallon in each of the 4 buckets , is it okay to keep adding R/O water or tap water until a low PPM is reached ? (I've read something about using florakleen letting it recirculate for a few hours?)

When switching over to flower nutes, is it necessary to clean the system aside from flushing out the old nutes? In DWC I would move my plants into another bucket, then clean with water and vinegar to remove the salt build up on the sides, how would one go about doing that in RDWC without removing plants or is it even necessary?

Dont worry about whats left unless your dealing with an issue.

redi jedi said:

Dont worry about whats left unless your dealing with an issue.

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Thanks redi Jedi , so no need to add an additional 3-5 gallons of water and drain it to lower the ppm ? Just drain as much as I can and add the new nutrients solution?

no cleaning needed either right ? only before a new grow ?

I just add water while my pump drains it to waste.Or you can fill then drain a few times.
If everything is happy Ill sometimes just remove half the water,refill and my ph stays stable this way.

If your flushing let plain water run 24hrs then dump and refill.
So drain then fill,wait 3 hrs drain,fill wait 24 hrs,drain fill.
This all depends if plants are happy.

Im a fan of letting the plants grow a bit then push them down with the screen.Your squares appear small so this makes it hard to bend plants down.

myke said:

Im a fan of letting the plants grow a bit then push them down with the screen.Your squares appear small so this makes it hard to bend plants down.

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thanks for the reply Myke , so if everything is healthy no need to drain out the last bit of water , just add the new soup ?

I researched a lot of scrog nets , kept finding a lot of people saying 2.5” squares on the bottom is better , top layer I have a 5” square net that I’ll add later ,

what’s your recommendation on scrog net square size for vegging?

when you get done with this grow, think about installing a drain in your system. i was lucky and have a floor drain next to my water heater that i ran pvc pipe to. open a valve and it all goes down the drain.

rkymtnman said:

when you get done with this grow, think about installing a drain in your system. i was lucky and have a floor drain next to my water heater that i ran pvc pipe to. open a valve and it all goes down the drain.

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I did install drain lines on the bottom of the 4 buckets minus the reservoir , I use a drain pump and pump it to buckets and drain them. I was asking about that little bit of water that’s left over , like 1/2 gal in each I would say , because the bulkhead has a few centimeters over the bucket bottom.

From the responses I’ve gotten , if plants are healthy no need to worry about the remaining little bit of water , when going into flowering nutes , is it necessary to flush before or clean?

After the this grow is done , is there any bottled cleaner that you run through the empty systems or just clean with plain water and vinegar for salt build up ?

I really appreciate everyone on this forum, for real!

AKTG said:

thanks for the reply Myke , so if everything is healthy no need to drain out the last bit of water , just add the new soup ?

I researched a lot of scrog nets , kept finding a lot of people saying 2.5” squares on the bottom is better , top layer I have a 5” square net that I’ll add later ,

what’s your recommendation on scrog net square size for vegging?

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My first bet was 3”. Now I run 4”. Seems easier to get my hands in. I only use one net

AKTG said:

I did install drain lines on the bottom of the 4 buckets minus the reservoir , I use a drain pump and pump it to buckets and drain them. I was asking about that little bit of water that’s left over , like 1/2 gal in each I would say , because the bulkhead has a few centimeters over the bucket bottom

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yep, that's why i installed my bulkheads on the bottom, not sides, of my totes. nothing left behind.

Yeah no biggy if theirs a little water left.

AKTG said:

After the this grow is done , is there any bottled cleaner that you run through the empty systems or just clean with plain water and vinegar for salt build up ?

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i bleached mine in between runs.

Also make sure you hand pour a few jugs through ea net pot. Your flushing the roots not the pails.

rkymtnman said:

i bleached mine in between runs.

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hey rkymtnnan ,

since the system is empty , I would assume any amount of bleach mixed with water is fine ? Or is there a ratio you run , 1 cup to a gallon?

myke said:

Also make sure you hand pour a few jugs through ea net pot. Your flushing the roots not the pails.

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Aaah I was under the impression this was done to clean the pales from building up salt algae or anything other microbes.
So the flush is for the roots to kind of reset for a bit , then add your new nutes ?

is it ok to hand pour through the hydroton in the net pots?As removing the kids would no longer be possible

AKTG said:

hey rkymtnnan ,

since the system is empty , I would assume any amount of bleach mixed with water is fine ? Or is there a ratio you run , 1 cup to a gallon?

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if you want to get technical, you can look up "what amount of bleach to sanitize". a cup to a gal sounds pretty good. maybe even a half cup? you just want to make sure you get bleach in all the nooks and crannies too.

AKTG said:

Aaah I was under the impression this was done to clean the pales from building up salt algae or anything other microbes.
So the flush is for the roots to kind of reset for a bit , then add your new nutes ?

is it ok to hand pour through the hydroton in the net pots?As removing the kids would no longer be possible

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Yup,either fill your system so roots are all submerged ,careful you can float your plants! Or just hand pour through the pebbles.

I go about 1" above bottom of net pot when flushing.

Loosk good!
No worries on the remaining water unless you have an issue like described above.
I have a very similar system as you, I use a Y splitter on my 3/4" line from my circulating pump. I can switch the valves on the Y to go back and forth between circulate and drain.

When I make the switch between veg and flower (just did like two days ago) I fill the system with RO water and something to sterilize. (Bleach, chlorine, or a strong dose of H202 like mentioned above works, but I use UC root)
Your scrog is nice, you have a lot of room to grow. Have you decide to flip to flower when. The screen is 75% or 100% full?