I'm using an overflow/siphon system somewhat like this to regulate the water level in my riparium and to make water changes easy. The important thing I have noticed is that the flow through a siphon tube when the ends are nearly the same height - very low head difference - the flow is also very low. But, if you are adding flow at a steady rate, that makes the water level rise a lot in the tank. In my case, with the very low water level it doesn't matter, but with the water up close to the top of the tank you would have serious overflow problems. You could manage this by having what looks like much too large a diameter siphon tubes. But to keep up with a cannister filter, giving you 200 gallons per hour, for example, would be very difficult. End result - it probably won't work.
If you were to drill the tanks, at the same level from the top of the tank, but below the desired water level, you could get around this problem by using 2 inch diameter interconnecting pipes. That would take away the flexibility you would have with the siphons though.