Rez size in RDWC?

Thread starter #1

Bluenoser

Well-Known Member
I'm building a RDWC setup, with only four 5 gal buckets right now, with the intent of expanding it in the future when I can buy more lighting to cover 6 buckets or maybe even 8 buckets later on.

What reservoir size should I use for the system?

Thanks for your info!
:)
 
Thread starter #3

Bluenoser

Well-Known Member
I just realized that the 106L tote rez I bought is not appropriate because the side of the rez is not flat, it has a ripple design, therefore my uniseal will not sit flush against it and therefore won't seal.

This gives me an opportunity to rethink the size requirement of the rez, something I had not thought about previously.

Hope someone out there has a suggestion :)
 

Bonsaiweed

Member of the Month: May 2018
Sorry...I figured one of those guys would answer. Just message one directly....they will answer you then. They may have missed the notification. It happens when a person follows a lot of threads. My notifications sometimes take weeks to catch up to me...

I would ask @Grandpa Tokin first....
 
Thread starter #7

Bluenoser

Well-Known Member
I'm just wondering if a 27L resivoir is too small for a four 5 gal RDWC setup or if I need a bigger rez for stability.

I had a 106L tote I was gonna use for a rez until I realized the uniseals could not be mounted flush on it because of the uneven design of the sides of it, (I returned it to Canadian Tire) so I'm shopping for a new rez container and want to get the right one for my system.

Also, not many people seem too concerned about the plastic for the rez being "food grade" plastic, but everyone seems to be sure to get food grade buckets, doh.
:)
 
I'm just wondering if a 27L resivoir is too small for a four 5 gal RDWC setup or if I need a bigger rez for stability.

I had a 106L tote I was gonna use for a rez until I realized the uniseals could not be mounted flush on it because of the uneven design of the sides of it, (I returned it to Canadian Tire) so I'm shopping for a new rez container and want to get the right one for my system.

Also, not many people seem too concerned about the plastic for the rez being "food grade" plastic, but everyone seems to be sure to get food grade buckets, doh.
:)
I don't like my reservoir line to get below half level. I have 50L so I can lose 25L before I top up add nuts, check PPM and PH level. I have to do this basically once a week. With only 27L you will be doing this every couple days, if your good with that.
Cheers
 

Grandpa Tokin

Member of the Month: Apr 2018
I don't like my reservoir line to get below half level. I have 50L so I can lose 25L before I top up add nuts, check PPM and PH level. I have to do this basically once a week. With only 27L you will be doing this every couple days, if your good with that.
Cheers
This is a good point. I only have 2 buckets so my res doesn’t need to be huge, but I like having enough so that I could leave it for a few days if needed. I’m in there daily anyway, but it’s nice to know I don’t have to. Once a week is awesome.
 
Thread starter #11

Bluenoser

Well-Known Member
Thanks for the reply grandpa!
I appreciate your input.
I see alot of the commercially made RDWC setups only have another 5gal bucket for the rez, by the sounds of it, this might be more labor intensive to manage.

So for a 4 bucket setup, a 50L rez should suffice?

Is there a point where it is overkill?

Seems that if you have to change the nutes every week or so, with a larger volume of water you will use up alot more nutes, which is more expensive.

Also, the bigger the rez, the more water I have to draw from my RO filter, which currently only has a 50gal/day membrane in it which is running really slow now (I've ordered a 100GPD one though which should arrive in a few weeks), so I have to put all that water into more buckets and store it up ahead of time so the water is ready to be dumped in the system, otherwise, the roots might dry out while I'm drawing all that water, which might take a whole day or more.

So much to consider.
 
Thanks for the reply grandpa!
I appreciate your input.
I see alot of the commercially made RDWC setups only have another 5gal bucket for the rez, by the sounds of it, this might be more labor intensive to manage.

So for a 4 bucket setup, a 50L rez should suffice?

Is there a point where it is overkill?

Seems that if you have to change the nutes every week or so, with a larger volume of water you will use up alot more nutes, which is more expensive.

Also, the bigger the rez, the more water I have to draw from my RO filter, which currently only has a 50gal/day membrane in it which is running really slow now (I've ordered a 100GPD one though which should arrive in a few weeks), so I have to put all that water into more buckets and store it up ahead of time so the water is ready to be dumped in the system, otherwise, the roots might dry out while I'm drawing all that water, which might take a whole day or more.

So much to consider.
I am probably doing it wrong but my plants are rocking so it works but I don't do a full water change except when the switch from veg to bloom. Weekly I top up and add nutrients based on the PPM measurement. Veg example and numbers are just for example sake. Water starts at 100 PPM (baseline) Added nutrients brings it to 600 PPM (500 PPM of added nutrients) after 1 week and half my water is used then PPM is down to 350 PPM so I top the water back up and add nutrients in this example half the original dose to bring it back up to the desired 600 PPM. So no I don't use additional water or additional nutrients but just maintain the desired level of both. If any of that makes sense. Watch your PH level as well very important and will help avoid a lot of issues.
 
I did that on my last grow with my NFT tube system, and ended up with root rot, but that might be because of heat issues, not necessarily a rez change issue.

I was told that my issues were because I did not change the nutes on a regular basis, can anyone else chime in on this and give their opinion?
Thanks! :)
Good to know, thank you. were you aerating the water, just curious as I thought lack of oxygen was the cause of root rot usually?
 
I had big airstones in the rez, but not in the tubes.
The tubes would overflow back into the rez, so there was also the waterfall effect.
I used hydrogen peroxide to stave off the bacteria and rot, and barely made it to the end of the grow unfortunately, but it all turned out OK.
Thanks for the info. Perhaps I have just been lucky so far but plants and roots look great 4 clones have gone from 3" tall to over 3 feet tall in 7 weeks and just flipped them. Fingers crossed I don't run into root rot and will keep an eye on it now. I learn more than I help but that's okay I hope. Will leave the rest to the experts.
Cheers and thanks again for sharing.
 

Bonsaiweed

Member of the Month: May 2018
Just food for thought..... I've read that higher reservoir temps cause the dissolved oxygen to escape the water. This causes root rot. Even with an air stone, temperatures do make a difference due to the amount of oxygen that can be retained in the water/nutrients.

Just trying to pass along information I've read......

Hope it helps.
 

Grandpa Tokin

Member of the Month: Apr 2018
I used a chiller this last flower run and absolutely love it. Hard to justify the expense, but I noticed a difference in root mass between chiller and no chiller. I also noticed it was much easier to maintain PH and the res seemed to produce less “slime,” for lack of a better word. I only flower 2 plants, but they are both well over 6 feet tall usually.

* Not trying to suggest people spend huge amounts of cash, just making conversation... :ganjamon:
 
Thread starter #20

Bluenoser

Well-Known Member
I'd love to have a chiller, but it's out of my $$$ range right now for sure.

My rez will be outside of the tent in a well insulated basement where it is cool in the summer, and the buckets and rez will be sitting directly on the cold cement floor. I'm hoping that keeps things relatively cool.

Has anyone tried wrapping some kind of insulation around the buckets to keep them cool before? Just a thought.