You may want to get a different type of feeder for your budgies.
I would be concerned about really young ones getting into that feeder and possibly getting stuck.
There are many different types of feeders you can choose from.
You can also simply scatter their seed on the fresh clean newspaper on top of the bottom grate in the cage after cleaning the cage each morning and evening.
This allows the budgies to "forage" for their seed and encourages them to utilize the entire cage.
I give my budgies 1 teaspoon of seed (each) in the morning and 1 teaspoon of seed (each) in the evening.