You shouldn’t need a reservoir with dwc. And air stones suck. If interested let me know I can help you improve your system. Get back to rodi water.
Im converting to a rdwc for 2 reasons more water = more stabe ph and 2 im going to have reservoir outside of tent to keep water cooler temp outside of temp is 10 degrees cooler than the inside of the tent it is also sealed so thats why outside is cooler so it keeps the inside at 76 77 degrees so that co2 stays in also ease of access to the reservoir and i dont have to go in continually to add water
How large is your grow space?
There are bulkhead fittings you can buy to mate to your totes/buckets. I would use totes for the increase in rez size and 2" bulkhead fittings with black ABS lines.
Air stones in general aren’t very good as you need finely atomized bubbles which carry liquid up to the base of net pot. Blue airstones are superior to all of the others and lots of air: I run a 950 GPH air pump to four stations and it’s not enough.
Got an Amazon link for those? 
I bought mine years ago at a local nursery supply. Let me dip in to A and see what I find:
Go to gh and get a farm kit. Takes two air lines. Run one down the sigt tube this will bubble right to the roots. The other hose to farm kit like rain from above.
If your able I could use some guidance on a Dwc setup just posted a new topic
Add a. farm kit