powerhead air injection proplems!

[bboyin4lyf]

hey , im just wondering why when my powerhead goes deeper into the tank water does the air injection reduce and then stop? incredibly annoying.
any help would be gladly appreciated, thanks

theres no holes in the air inlet tube but somehow water still seems to get into the tube and stop the air flow.

I cant work it out !

 

[Anonymous]

The venturi is not strong enough to overcome the hydrostatic pressure, and there is nothing you can do about it other than change the pump, the venturi, or both. Unless it is due to some clog in the venturi that you can clean and remove, it is pure physic, and "normal."

(It is like an air pump that only good for 12 inch of water, and if you push the air tubing deeper and deeper, the bubble will get less and less, until it totally stopped, even the pump keep running all the time.)