Chiller noise

[angelscrx]

My chiller has started to make a strange gurgling rattling noise. it just started today and has never made it before. It is not rocking and the water is coming through fine. Tank temp is fine too. Help?

 

[Tex]

May I ask, what brand and size of chiller is it?

 

[angelscrx]

It's a prime brand and it's a 1/4 hp. I have 150g tank w/ sump.

 

[angelscrx]

Does anyone have any experience with this or a suggestion on what to do? The noise is getting annoying. Thanks