css125 troubleshooting...help?

[str8clownr]

my css 125 that i just installed stop making bubbles when i tried to put it in the sump, so i put it back on the tank but still no bubbles..... what can i do?

[Joshua1023]

Check that airline is clear of obstructions. Unplug airline from silencer. Make sure the pump input is no deeper than three inches from the surface of the water. If deeper than three inches trim tubing to correct. Make certain that where the air tube plugs onto the venturi is free of salt creep inside. Pour a little fresh water into that hole to be certain.

It must be one of those things.