Airlocks

[jmkgreen]

So my JBL e1500 has been in operation a few days now but every day I'm having to stop it, push the syphoning button and rattle it around then switch it back on again to get rid of trapped air. Makes an awful screaming sound otherwise.

I didn't have anywhere near this much trouble with my Eheim 2075. Could air actually be getting in at all? Or is there some other explanation?