sump gurgles?

[darb2]

About every 15 min the overflow into my gurggles. I thought I had it set up properly, it wasnt doint it last week. I have tried to adjust it, but I am new to sumps. Thanks

[Anemoneman]

Need some more details on your piping arrangement in order to help.

[darb2]

There are 2 holes drilled in the bottom of the tank. the return , and the supply. The overflow is threaded to the bulkhead and is a 1"tube that is almost the full height of the tank. Around the 1" tube there is a 2" tube that has a strainer at the bottom and at the top. The bottom looks like a typical strain on a filter. The strainer at the top has a cup shape that is open at the top. Inside that cup there is a cap/lid with a hole in it at the center. In the hole there is a piece of rigid 1/8" tube that goes down in the overflow. If the 1/8" tubing is raised or lowered the water level in the tank will lower or raise.
As I read this beck, before sending it types way more complicated than it looks

[darb2]

bump

[fishfreek]

is the airline tubing open? The airline tube should alow the overflow to breath. If for some reason the airline tubing has some dried up saltwater in it then air might not be getting thru it as well and thust the gurling.

[darb2]

The air tube is open. Now the sound is getting more frequent