A good set of stand-pipes will stop the gurguling noise.
CPR makes overflow boxes that are hang on, I use a CPR100 on my 52g with a sealife systems 175g rated wet/dry.
on my 210 I use durso stand pipe and they are quieter then my CPR100
That's not a planted tank. That's a jungle with glass around it- MFDROOKIE Circa 2011