DWC 4 Site Tote?

I only need 1 pump and 1 airstone for a 20 gal tote/Four 6" sites??? To me it seems like i need more than just 1 of each??? No? And if i were to get another pump or airstone is there advantages ?? Or just 1 of each is fine as is?

i would throw two or three in there for more oxygen and to keep ur water moving

I have two 10" in my 18 gallon tote, I was going to do a combo Aero/dwc, but my water pump broke. So now its just a DWC. Been thinking of adding another airstone, but everything checking out just fine so far.