I have 2 ladders of 8-9' each, but they only have 50-60 taps on them. I build them with the main line running into a T which splits the flow to go 2 ways at 90 degrees from the main. My mains are 1" but the tee reduces the 2 sides to 3/4". Then about 4-5" on the 3/4 there is an elbow and each has a riser in 3/4" for the height of the sap ladder. Then the 2 recombine into 1 the same as the bottom and the sap flows out the 1" main. I have a ball valve on one leg only and I adjust that to get the best flow from the system the first day I have real good flow. I then put a needle valve to add a very tiny amount of air about 30' upstream from that lower tee. I open that a tiny bit and watch the flow. It takes very little to make it work real good.
Breezy Acres may chime in, he has perfected sap ladders. I had mine long before I learned how he does them, but I think he found that 1/2" risers work best. If you have 700 taps you will need a few risers and he can tell you how to do it. I have no pictures but he has some in his pics. I think even with 700 taps you only need a very small amount of air. The air gives the lift for the sap or some say that the sap rides the bubbles up.
Make sure you have enough pump, sap ladders require good vacuum and CFM.
If I rebuild mine again, I'll use Breezy Acres method and sizing formula to know how many risers to use. I have 2 other ladders that use star fittings and 5/16 risers, the larger tubes work better for me and it will be far easier to build for your larger system.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.