A magnetic stir and some sort of auto top off would help replenish the water and the magnetic stirring would keep things in suspension.Yes... splitting the output has its limitations. Every tank would have to get fed the same number of times per day and the same amounts. Your system is better as it allows you to customize based on the needs of individual tanks.
Did I understand the link you provided correctly... do you actually feed into the return chamber and have you pump too the feeding?
I can see how substituting fluid for air in my design would be an improvement. But my design doesn't include a method to stir the contents, which would be necessary as the food would settle to the bottom.