Pros and Cons of 8 gallon vs 13 gallon pots for RDWC system

I’ve got a 4x8 tent and going with either 4 or 6 buckets.
I’m going to build up a RDWC system.

This will be going into a basement where I have access to a sink/water coming off our well.
Space isn’t really a concern. I’ll use a 4x8 for flowering and 4x4 for veg and 4x4 for drying.

I’m looking at buckets that are either 8 or 13 gallons.

Pros of 13 over 8
More volume for stability
Less volatile temp changes
Fewer water changes

Cons of 13 over 8
Managing more water
More nutrients
Larger containers

I’ve done aquaponics for many years doing flood and drain and constant flood, so I’m cool with measuring ph, ec and managing temps and nutrients.
I really dig automation and use a niwa grow hub and raspi controllers I build.

What is you’alls take on the different sizes for buckets in a RDWC system?

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I say if you have the height use the larger pails.

You only fill it once all the way. The plants drink what they drink no matter the size pail it’s the same amount of water to add when they are growing. Same nutrients so no difference except larger is easier to control ph and temps and ppm.
Water changes , huh ? Only if there is a major issue which I never have had. So yeah 0 water changes , just topping off. Or better yet a fill valve on a float so it does the work and not you.

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My tents will be 6’ tall…would you consider that high enough to deal with plants in the 13 gallon pots?

I was under the impression that it was necessary to change the water every so often, if that’s not the case that makes my planning way easier.

I realize that responding to issues may necessitate cleaning out the nutrients, but thought the water also had to be switched out on some frequency.

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I think a 6foot tent is to short for the taller buckets.

In my case I dont change the water. This is my system that I have dialed in for perfect temps and well almost perfect conditions. It takes time to get hydro down perfect due to outside climate changes and differences. Two identical systems may need to be run 2 different ways. Every location is different and calls for it’s own adjustments.
It isn’t a bad idea to have a way to quick drain a system and refill it. But I use an RO system with a filler on a float and nothing is fast with an RO. I think it took 2 days to fill.


A lot of growers use yellow topped totes: I prefer the 19 gallon one (full about 12 gallons).

A small submersible pump makes emptying the rez pretty simple. You may or may not need to drain/fill (I do) but that gives you the flexibility.

This implies you will have all buckets connected and a standing reservoir as well? Check rez? Having something outside the grow space as a larger reservoir is not a bad idea. I picked up a couple of plastic 30 gallon barrels from the local car wash (soap not wax) and turned them each into a suitable reservoir: one for filling with R/O and the other in the system.

Managing for temperature is important as well: your basement may be stable enough to not need a chiller but again; a standing reservoir outside the grow space can help.

Before you start look into the people using the Jack’s 3-2-1 system: very affordable and very good nutrient line by J. R. Peters.


My plan is to use 8 or 13 gallon buckets with the reservoir outside the tent, and a backup reservoir connected to that on a float to keep it full.
My tent is 4 x 8 x 6.5.

I’ve been collecting temp and humidity measurements in the basement. It’s more stable than the house but I wouldn’t be surprised to find i’ll need a chiller in the summer and heater in the winter.

I’d dig setting up a grolab system but the wife says it’s not time yet…

So how good does it do to say bury the rez tank in the ground in a basement to keep stable temps. Ive seen a guy on utube dug a hole on the basement buried the tank to keep the. water temps in check

I looked into setting up something similar although in my case was going to bury some copper tubing and run coolant through as a heat exchanger. No reason it wouldn’t work.

If I take a jackhammer and bust open the floor of the basement to bury my reservoir I will lose wife approval quickly.
She’s totally cool with even building a whole room, multiple tents and everything so far…so I’m not going to push it!

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Welcome to the forum! :clap:t2::clap:t2:
How big of a basement are we talking about here?
And if I may ask, why not rooms instead of tents?
Always enjoy envying others grow space… lol

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If I had a big house I would have all grow rooms and a kitchenbathbedlivingroom in the corner lmao

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I have a sink in my grow room now and it’s like gold. I will never have a grow room without one. Just wished I had two more rooms just like it.

The basement is large, so I have enough room to start growing in my tent while building a grow room.
I’m planning on dividing the room so I can veg, flower and germinate or grow other things at the same time…but dang the price of lumber and building materials right now…


I have a plumber coming to install a sink in my basement, and while it looks hard as the pipes are on the other side of the house…I really want a sink in the grow room when i build it out.

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So happy I had a drain for a utility tub installed in the basement when I had the house built a decade ago. That’s the grow room.