RDWC but keeping nutes and water low: water displacement?

[NewGreen]

Hi everyone (I'm new here),
I've been growing DWC (shared tote with 4 net pots) for over a year. It works, but it's a bit limited by the small volume 15L/4Gallon tote- once root mass comes into play, it regularly requires top-ups every 1-2 days(probably go through 25-30L/week depending on stage).

I decided it was time to upgrade my entire grow setup, and instead of having multiple DWC's with 1 net pot in each, it would be simpler to build an RDWC. However, the biggest caveat I see with such a system is the massive amount of water and nutrients are going to be necessary throughout the entire grow. For point of reference was looking at 5x 8gallon/30L buckets. Even filled halfway, I'm not confidant that

1. The airstone will be able to produce a mist high enough to hit the net pot/hydroton
2. That's still 20Gallons/75L a week. Which to me seems excessive depending on the stage.

I can see this being less of an issue with mature roots, because of water displacement, but that still seems early stages will have massive amounts of nutes/water "waste". Building it with smaller buckets would solve the early stage issue, but then as they mature, I'll be right back topping up every 2 days to keep feeding the plants. I could use my old setup as an early veg stage, and then move them to the RDWC, but "transplanting" them may prove difficult if the roots get as tangled as they do now in my current DWC.

So my question is: Is there a "large safe bulk material" I can put at the bottom of the buckets to displace the water, that allow easy drainage, is PH inert, that I can slowly remove as the roots start adding their own volume? It'd be amazing if I could source hydroton(Clay Pebbles) at 4"/10cm diameters(lets call them Clay Baseballs at that point), so it would be easy to add/remove as needed, without worrying about clogging pvc or root entanglement.

Basically I'm trying to keep my grow costs reasonable, but have the room to grow as needed.

 

[The Phantom]

Find a way to reuse your water if you can. Using my 80 gallons every week to water a garden and landscaping in the desert made me feel better about weekly water changes. I use a super cheap fertilizer and my water bill has gone up maybe $5-10.

In all seriousness look into using some sort of fabric bag to use in your current dwc to grow out your plants in without tangling the roots too much. Find the bags they use for Dutch buckets, get 1 for each plant. Then you can do as you say and "up pot" them to your bigger setup. That should get you pretty close to perpetual growing if you do it right.

 

[NewGreen]

Thanks for the reply. A "sock" for the DWC net pots is a good idea. Not sure exactly what those are called, one google suggested nylon bags used for paint straining.

As for re-using my water/nutes, not really an option for me as I live in Canada. We will be experiencing winter soon enough, so my outdoor garden isn't going to benefit from it. The other possibility for me is aeroponic to keep nutes/water waste down, but those have their own cons.

 

[The Phantom]

You could probably even find filter socks the same diameter as your net pots and in whatever micron size. I think I've heard of people using laundry bags for delicates in the washer.